Restatement (Third) of Foreign Relations Law of the United States § 101 (Am. L. Inst. 1987) [hereinafter Third Restatement]. Although originally limited to nation-to-nation relations, international law grew in the 20th century with the fields of human rights law and international criminal law to regulate individuals' conduct in some circumstances. See, e.g., G.A. Res. 217 (III) (Dec. 10, 1948); Geneva Convention Relative to the Treatment of Prisoners of War, Aug. 12, 1949, 6 U.S.T. 3316, 75 U.N.T.S. 135; Geneva Convention Relative to the Protection of Civilian Persons in Time of War, Aug. 12, 1949, 6 U.S.T. 3516, 75 U.N.T.S. 287; G.A. Res. 2200A (XXI) (Dec. 16, 1966; U.N. GAOR, 21st Sess., 1496th plen. mtg., U.N. Doc. A/RES/2200A (XXI) (Dec. 16, 1966).

See, e.g., Ware v. Hylton, 3 U.S. (3 Dall.) 199, 281 (1796) ("When the United States declared their independence, they were bound to receive the law of nations, in its modern state of purity and refinement."); Chisholm v. Georgia, 2 U.S. (2 Dall.) 419, 474 (1793) ("[T]he United States had, by taking a place among the nations of the earth, become amenable to the law of nations."); Letter from Thomas Jefferson, Sec'y of State, to Edmond Charles Genet, French Minister (June 5, 1793), in Jefferson Papers, https://founders.archives.gov/documents/Jefferson/01-26-02-0189 (describing the law of nations as an "integral part" of domestic law).

See infra "Forms of International Commitments."

U.S. Const. art. II, § 2, cl. 2.

As used in this report, the term commitment is a generic term intended to encompass all forms of legally binding agreements and non-binding instruments.

See infra "Forms of International Commitments."

See infra "Effects of International Agreements on U.S. Law."

See, e.g., Third Restatement, supra note 1, § 102(2).

The Paquete Habana, 175 U.S. 677, 700 (1900).

See infra "Relationship Between Customary International Law and Domestic Law."

For further detail of various types of international commitments and their relationship with U.S. law, see Cong. Rsch. Serv., 106th Cong., Rep. on Treaties and Other International Agreements: The Role of the United States Senate 43–97 (Comm. Print 2001) [hereinafter Treaties and Other International Agreements], available at https://www.govinfo.gov/content/pkg/CPRT-106SPRT66922/pdf/CPRT-106SPRT66922.pdf; Curtis A. Bradley & Jack L. Goldsmith, Presidential Control Over International Law, 131 Harv. L. Rev. 1201, 1207–09 (2018).

Restatement (Fourth) of the Foreign Relations Law of the United States § 301 cmt. a (Am. L. Inst. 2018) [hereinafter Fourth Restatement]. See also James M. Inhofe National Defense Authorization Act for Fiscal Year 2023, Pub. L. No. 117-263, 136 Stat. 2395, 2600 (2022) (to be codified in 1 U.S.C. § 112b(k)(4)(A)) [hereinafter 2023 NDAA].

See Vienna Convention on the Law of Treaties art. 2, Apr. 24, 1970, 1155 U.N.T.S. 331 [hereinafter Vienna Convention]. Although the United States has not ratified the Vienna Convention, courts and the executive branch generally regard it as reflecting customary international law on many matters. See, e.g., De Los Santos Mora v. New York, 524 F.3d 183, 196 n.19 (2d Cir. 2008) ("Although the United States has not ratified the Vienna Convention on the Law of Treaties, our Court relies upon it 'as an authoritative guide to the customary international law of treaties,' insofar as it reflects actual state practices.") (quoting Avero Belg. Ins. v. Am. Airlines, Inc., 423 F.3d 73, 80 n.8 (2d Cir. 2005)); Fujitsu Ltd. v. Fed. Express Corp., 247 F.3d 423, 433 (2d Cir. 2001) ("[W]e rely upon the Vienna Convention here as an 'authoritative guide to the customary international law of treaties.'") (quoting Chubb & Son, Inc. v. Asiana Airlines, 214 F.3d 301, 309 (2d Cir. 2000)). But see Third Restatement, supra note 1, § 208 reporters' n.4 ("[T]he [Vienna] Convention has not been ratified by the United States and, while purporting to be a codification of preexisting customary law, it is not in all respects in accord with the understanding and the practice of the United States and of some other states."); The Administration's Proposal for a U.N. Resolution on the Comprehensive Nuclear Test-Ban Treaty: Hearing Before the Sen. Comm. on Foreign Relations, 114th Cong. (2016) (statement of Stephen G. Rademaker, Principal, The Podesta Grp.), https://www.foreign.senate.gov/download/090716_rademaker_testimony [hereinafter Rademaker Statement] ("[T]he more correct statement with respect to the Vienna Convention would be that in the opinion of the Executive branch it generally reflects customary international law, but, in the opinion of the Senate, in important respects it does not.").

See, e.g., 2023 NDAA, 136 Stat. 2600 (codified in 1 U.S.C. § 112b(k)(4)(A)); Fourth Restatement, supra note 12, § 301 cmt. a. Under U.S. law, the term treaty is not always interpreted to refer only to those agreements described in Article II, Section 2, of the Constitution. See Weinberger v. Rossi, 456 U.S. 25, 31–32 (1982) (interpreting statute barring discrimination except where permitted by "treaty" to refer to both treaties and executive agreements); B. Altman & Co. v. United States, 224 U.S. 583, 601 (1912) (construing the term treaty, as used in statute conferring appellate jurisdiction, to also refer to executive agreements).

Fourth Restatement, supra note 12, § 301 cmt. a. See also 2023 NDAA, 136 Stat. 2600 (codified in 1 U.S.C. § 112b(k)(4))

See 2023 NDAA, supra note 14; Fourth Restatement, supra note 12, § 301 cmt. a.; Weinberger, 456 U.S. at 31–32 (1982); B. Altman, 224 U.S. at 601.

See infra "Executive Agreements."

See infra Non-Binding Instruments."

See Fourth Restatement, supra note 12, § 301 cmt. a.

See id. § 304 cmt. a ("Some agreements provide that they are binding upon signature alone, although signature ad referendum (that is, subject to confirmation through some subsequent act) is frequently employed."); Curtis A. Bradley, Unratified Treaties, Domestic Politics and the U.S. Constitution, 48 Harv. Int'l L.J. 307, 313 (2007) ("Under modern practice ... consent is manifested through a subsequent act of ratification—the deposit of an instrument of ratification or accession with a treaty depositary in the case of multilateral treaties, and the exchange of instruments of ratification in the case of bilateral treaties.").

For additional background on the Treaty Clause, see Cong. Research Serv., Treaty Clause: Overview of the President's Treaty-Making Power, Constitution Annotated, https://constitution.congress.gov/browse/essay/artII-S2-C2-1-1/ALDE_00012952/ (last visited Jan. 12, 2023).

See, e.g., Louis Henkin, Foreign Affairs and the U.S. Constitution 177 (2d ed. 1996); Arthur Bestor, "Advice" from the Very Beginning, "Consent" When the End Is Achieved, 83 Am. J. Int'l L. 718, 726 (1989).

See supra note 22.

On the occasion that scholars have described as the first and last time the President personally visited the Senate chamber to receive the Senate's advice on a treaty, President Washington went to the Senate in August 1789 to consult about proposed treaties with the Southern Indians. See 1 Annals of Cong. 65–71 (1789). Observers reported that he was so frustrated with the experience that he vowed never to appear in person to discuss a treaty again. See, e.g., William Maclay, Sketches of Debate in the First Senate of the United States 122–24 (George W. Harris ed., 1880) (record of the President's visit by Senator William Maclay of Pennsylvania); Ralston Hayden, The Senate and Treaties, 1789–1817, at 21–26 (1920) (providing a historical account of Washington's visit to the Senate).

See Memoirs of John Quincy Adams 427 (Charles Francis Adams ed., 1875) ("[E]ver since [President Washington's first visit to the Senate to seek its advice], treaties have been negotiated by the Executive before submitting them to the consideration of the Senate.").

See Zivotofsky v. Kerry, 576 U.S. 1, 13 (2015) ("The President has the sole power to negotiate treaties.... "); United States v. Curtiss-Wright Export Corp., 299 U.S. 304, 319 (1936).

Accord Curtis A. Bradley & Jack L. Goldsmith, Treaties, Human Rights, and Conditional Consent, 149 U. Pa. L. Rev. 399, 405 (2000) ("The exercise of the conditional consent power has been in part a response by the Senate to its loss of any substantial 'advice' role in the treaty process."); Samuel B. Crandall, Treaties, Their Making and Enforcement 81 (2d ed. 1916) ("Not usually consulted as to the conduct of negotiations, the Senate has freely exercised its co-ordinate power in treaty making by means of amendments.").

As a general matter, "[r]eservations change U.S. obligations without necessarily changing the text, and they require the acceptance of the other party." See Treaties and Other International Agreements, supra note 11, at 11. Accord Fourth Restatement, supra note 12, § 305 reporters' n.2 ("Although the Senate has not been entirely consistent in its use of the labels, in general the label ... 'reservation' [has been used] when seeking to limit the effect of the existing text for the United States.").

Understandings are "interpretive statements that clarify or elaborate provisions but do not alter them." Treaties and Other International Agreements, supra note 11, at 11. Accord Fourth Restatement, supra note 12, § 305 reporters' n.5.B ("The Senate has regularly used 'understandings' to set forth the U.S. interpretation of particular treaty provisions.").

Declarations are "statements expressing the Senate's position or opinion on matters relating to issues raised by the treaty rather than to specific provisions." Treaties and Other International Agreements, supra note 11, at 11. See also Fourth Restatement, supra note 12, § 305 reporters' n.5.E ("The Senate sometimes uses 'declarations' to express views on matters of policy.").

For additional background on RUDs, see CRS In Focus IF12208, Reservations, Understandings, Declarations, and Other Conditions to Treaties, by Stephen P. Mulligan.

See, e.g., Resolution of Advice and Consent to Ratification of Protocols to the North Atlantic Treaty of 1949 on the Accession of the Republic of Finland and the Kingdom of Sweden § 3, S. Treaty Doc. 117-3, available at https://www.congress.gov/treaty-document/117th-congress/3/resolution-text (providing advice and consent subject to the condition that the President make certain certifications to the Senate).

See, e.g., Resolution of Advice and Consent to Ratification of the Food Aid Convention 1999 § 3(b), S. Treaty Doc.106-4, available at https://www.congress.gov/treaty-document/106th-congress/14/resolution-text (providing advice and consent subject to the provision that "Nothing in the Convention requires or authorizes legislation or other action by the United States of America that is prohibited by the Constitution of the United States as interpreted by the United States").

Procedural matters include requirements that the President make certifications to the Senate, produce reports, or consult certain congressional committees on issues the treaty raises. See Treaties and Other International Agreements, supra note 11, at 11; Fourth Restatement, supra note 14, § 305 reporters' n.2.

Fourth Restatement, supra note 12, § 305 reporters' n.4. See also United States v. Stuart, 489 U.S. 353, 374–75 (1989) (Scalia, J., concurring) ("[The Senate] may, in the form of a resolution, give its consent on the basis of conditions. If these are agreed to by the President and accepted by the other contracting parties, they become part of the treaty and of the law of the United States.... ").

For discussion of historical examples of conditions attached by the Senate to treaties, see Fourth Restatement, supra note 12, § 305 reporters' n.5.

For example, in giving its advice and consent to the first treaty that was to be ratified by the United States after the adoption of the Constitution—dubbed the Jay Treaty because it was negotiated by the first Supreme Court Chief Justice of the United States, John Jay, who was appointed a special envoy to Great Britain despite his role in the judicial branch—the Senate insisted on suspending an article allowing Great Britain to restrict U.S. trade in the British West Indies. S. Exec. Journal, 4th Cong., Spec. Sess. 186 (1795). Great Britain ratified the Jay Treaty without objection to the Senate's changes. See Hayden, supra note 24, at 86–88.

See infra notes 40–42 (discussing historical usage of executive agreements and related judicial opinions).

See, e.g., Am. Ins. Ass'n v. Garamendi, 539 U.S. 396, 415 (2003) ("[O]ur cases have recognized that the President has authority to make 'executive agreements' with other countries, requiring no ratification by the Senate or approval by Congress, this power having been exercised since the early years of the Republic."); Dames & Moore v. Regan, 453 U.S. 654, 680 (1981) (recognizing presidential power to settle claims of U.S. nationals and concluding "that Congress has implicitly approved the practice of claim settlement by executive agreement"); United States v. Belmont, 301 U.S. 324, 330 (1937) ("[A]n international compact ... is not always a treaty which requires the participation of the Senate.").

See, e.g., Garamendi, 539 U.S. at 415 (discussing "executive agreements to settle claims of American nationals against foreign governments" dating back to "as early as 1799"); Act of Feb. 20, 1792, ch. 8, § 26, 1 Stat. 239 (act passed by the Second Congress authorizing postal-related executive agreements).

See Treaties and Other International Agreements, supra note 11, at 38; Oona A. Hathaway, Treaties' End: The Past, Present, and Future of International Lawmaking in the United States, 117 Yale L.J. 1236, 1288 (2008); Bradley & Goldsmith, supra note 11, at 1210.

Bradley & Goldsmith, supra note 11, at 1213. See also Treaties and Other International Agreements, supra 11, at 40.

Congress sometimes enacts legislation that pre-authorizes the President to conclude executive agreements on certain subjects or within certain parameters. See, e.g., CLOUD Act, Pub. L. No. 115-141, div. V, § 105, 132 Stat. 1213, 1217 (2018) (codified at 18 U.S.C. § 2523) (authorizing data-sharing executive agreements with certain foreign nations); Foreign Assistance Act of 1961, Pub. L. No. 87-195, 75 Stat. 424 (codified as amended at 22 U.S.C. §§ 2151–2431k) (authorizing the President to furnish assistance to foreign nations "on such terms and conditions as he may determine, to any friendly country"). Pre-authorized agreements are sometimes referred to as ex ante agreements. On other occasions, Congress enacts legislation approving agreements that the President already negotiated and signed. See, e.g., United States-Mexico-Canada Agreement Implementation Act, Pub. L. No. 116-113, § 101 (2020) (providing approving for the United States-Mexico-Canada Agreement Implementation Act). Agreements authorized after conclusion are sometimes referred to as ex post agreements.

See Third Restatement, supra note 1, § 303(3); Treaties and Other International Agreements, supra note 11, at 86.

See Treaties And Other International Agreements, supra note 11, at 88. See also supra note 39 (citing Supreme Court case law recognizing the validity of sole executive agreements).

For background on methods of legislative approval for congressional-executive agreements, see supra note 43.

The Second Congress enacted legislation in 1792 authorizing the postmaster general to "make arrangements with the postmasters in any foreign country for the reciprocal receipt and delivery of letters and packets, through the post offices." Act of Feb. 20, 1792, ch. 8, § 26, 1 Stat. 239.

United States v. Curtiss-Wright Export Corp., 299 U.S. 304, 318 (1936).

See B. Altman & Co. v. United States, 224 U.S. 583, 601 (1912) ("While it may be true that this commercial agreement, made under authority of the tariff act of 1897, § 3, was not a treaty possessing the dignity of one requiring ratification by the Senate of the United States, it was an international compact, negotiated between the representatives of two sovereign nations, and made in the name and on behalf of the contracting countries, and dealing with important commercial relations between the two countries, and was proclaimed by the President. If not technically a treaty requiring ratification, nevertheless it was a compact authorized by the Congress of the United States, negotiated and proclaimed under the authority of its President.").

Congress authorizes congressional-executive agreements through legislation enacted through the bicameral process, which involves both houses of Congress. For background on bicameralism, see Cong. Research Serv., Bicameralism, Constitution Annotated, https://constitution.congress.gov/browse/essay/artI-S1-3-4/ALDE_00013293// (last visited June 21, 2023).

See Treaties and Other International Agreements, supra note 11, at 5.

North American Free Trade Agreement, Can.-Mex.-U.S., Dec. 17, 1992, 32 I.L.M. 605 (entered into force Jan. 1, 1994).

See General Agreement on Tariffs and Trade, Oct. 30, 1947, 61 Stat. A3.

See Wilson v. Girard, 354 U.S. 524, 526–30 (1957) (giving effect to administrative agreement authorized under the bilateral U.S.-Japan Security Treaty).

For example, the United States acquired the naval base at Guantanamo Bay, Cuba, through an executive agreement authorized by a 1903 treaty. See CRS Report R44137, Naval Station Guantanamo Bay: History and Legal Issues Regarding Its Lease Agreements, by Jennifer K. Elsea, at 7.

The binational International Boundary and Water Commission, for example, was created by a series of U.S.-Mexico treaties and is authorized to make decisions, called "minutes," that the United States can approve on a case-by-case basis. See CRS Report R45430, Sharing the Colorado River and the Rio Grande: Cooperation and Conflict with Mexico, by Nicole T. Carter, Stephen P. Mulligan, and Charles V. Stern, at 3.

See, e.g., Crandall, supra note 27, at 179–119 (discussing acceptance of U.S.-British boundary delimitation).

See Treaties and Other International Agreements, supra note 11, at 86–87 n.117 (discussing examples in which Members of the Senate contended that certain executive agreements did not fall within the purview of an existing treaty and required Senate approval).

See Am. Ins. Ass'n v. Garamendi, 539 U.S. 396, 415 (2003) ("[O]ur cases have recognized that the President has authority to make 'executive agreements' with other countries, requiring no ratification by the Senate or approval by Congress."); Dames & Moore v. Regan, 453 U.S. 654, 680 (1981); United States v. Belmont, 301 U.S. 324, 330 (1937).

See Treaties and Other International Agreements, supra note 11, at 5 (citing U.S. Const. art. II, § 1, cl. 1 (executive power), § 2, cl. 1 (commander in chief power, treaty power), § 3 (receiving ambassadors)).

Garamendi, 539 U.S. at 415; Dames & Moore, 453 U.S. at 680; United States v. Pink, 315 U.S. 203, 229 (1942); Belmont, 301 U.S. at 330.

See Treaties and Other International Agreements, supra note 11, at 88. See also Belmont, 301 U.S. at 330 (recognizing constitutional authority for the Litvinov Assignment); Pink, 315 U.S. at 229 (confirming the holding in Belmont).

See Third Restatement, supra note 1, § 303(4). See also Zivotofsky v. Kerry, 135 S. Ct. 2076, 2084–96 (2015) (recognizing that the Constitution confers the President with exclusive authority to recognize foreign states and their territorial bounds and striking down a statute that impermissibly interfered with the exercise of such authority).

See Dames & Moore, 453 U.S. at 680 ("Crucial to our decision today is the conclusion that Congress has implicitly approved the practice of claim settlement by executive agreement.").

See id. at 686 (upholding sole executive agreement concerning the handling of Iranian assets in the United States despite the existence of a potentially conflicting statute given Congress's historical acquiescence to these types of agreements). But see Medellín v. Texas, 552 U.S. 491, 531–32 (2008) (suggesting that Dames & Moore analysis regarding significance of congressional acquiescence might be relevant only to a "narrow set of circumstances," where presidential action is supported by a "particularly longstanding practice" of congressional acquiescence).

While the exact framework that the Supreme Court would use to evaluate a sole executive agreement that Congress expressly opposes is not settled, in separation-of-powers cases, the Supreme Court has sometimes adopted the reasoning of Justice Jackson's concurring opinion in Youngstown Sheet & Tube Co. v. Sawyer, which explained that the President's constitutional powers "are not fixed but fluctuate, depending on their disjunction or conjunction with those of Congress." 343 U.S. 579, 635 (1952). See also, e.g., Zivotofsky, 135 S. Ct. at 2083, 2096 (citing and relying, in part, on Justice Jackson's concurrence). Under Justice Jackson's framework, the President's authority could be considered at its "lowest ebb" when concluding a sole executive agreement in direct opposition to Congress's expressed will. See Youngstown Sheet & Tube, 343 U.S. at 637–38. At the "lowest ebb," the President could conclude a sole executive agreement only if it fell within a constitutional power that was "at once so conclusive and preclusive" that Congress cannot regulate the issue. See id.

See Harold Hongju Koh, Triptych's End: A Better Framework to Evaluate 21st Century International Lawmaking, 126 Yale L.J. F. 338, 345 (2017); Daniel Bodansky & Peter Spiro, Executive Agreements+, 49 Vand. J. Transnat'l L. 885, 887 (2016).

See Bodansky & Spiro, supra note 67 at 927; Koh, supra note 67, at 345–48.

See Digest of U.S. Practice in International Law 2012, at 95 (Carrie Lyn D. Guymon ed., 2012). The Obama Administration made similar arguments concerning its authority to conclude the Paris Agreement on climate change and the Minamata Convention on Mercury. See CRS Report R44761, Withdrawal from International Agreements: Legal Framework, the Paris Agreement, and the Iran Nuclear Agreement, by Stephen P. Mulligan, at 18 nn. 145–148; Press Release, U.S. Dep't of State, United States Joins Minamata Convention on Mercury (Nov. 6, 2013), https://2009-2017.state.gov/r/pa/prs/ps/2013/11/217295.htm.

See Bradley & Goldsmith, supra note 11, at 1263.

Compare Bradford C. Clark, Domesticating Sole Executive Agreements, 93 Va. L. Rev. 1573, 1661 (2007) (arguing that the text and drafting history of the Constitution support the position that treaties and executive agreements are not interchangeable); Laurence H. Tribe, Taking Text and Structure Seriously: Reflections on Free-Form Method in Constitutional Interpretation, 108 Harv. L. Rev. 1221, 1249–67 (1995) (arguing that the Treaty Clause is the exclusive means for Congress to approve significant international agreements); John C. Yoo, Laws as Treaties?: The Constitutionality of Congressional-Executive Agreements, 99 Mich. L. Rev. 757, 852 (2001) (arguing that treaties are the constitutionally required form for international agreements concerning action outside of Congress's Article I powers, including matters with respect to human rights, political/military alliances, and arms control, but are not required for Congress's enumerated powers, such as agreements concerning international commerce); with Third Restatement, supra note 1, § 303 n.8 ("At one time it was argued that some agreements can be made only as treaties, by the procedure designated in the Constitution.... Scholarly opinion has rejected that view."); Henkin, supra note 22, at 217 ("[I]t is now widely accepted that the Congressional-Executive agreement is available for wide use, even general use, and is a complete alternative to a treaty.... "); Bruce Ackerman & David Golove, Is NAFTA Constitutional?, 108 Harv. L. Rev. 799, 861–96 (1995) (arguing that developments in the World War II era altered historical understanding of the Constitution's allocation of power between government branches so as to make congressional-executive agreement a complete alternative to a treaty).

See, e.g., Wallace McClure, International Executive Agreements (1941); Edwin Borchard, Shall the Executive Agreement Replace the Treaty?, 53 Yale L.J. 664 (1944); Myers S. McDougal & Asher Lans, Treaties and Congressional-Executive or Presidential Agreements: Interchangeable Instruments of National Policy (Pt. I), 54 Yale L.J. 181 (1945).

See, e.g., Ackerman & Golove, supra note 71, at 681–96; Tribe, supra note 71, at 1249–67.

Compare, e.g., Steven Groves, The Paris Agreement is a Treaty and Should be Submitted to the Senate, Backgrounder No. 3103 (Heritage Foundation, March 15, 2016), http://thf-reports.s3.amazonaws.com/2016/BG3103.pdf (arguing that the Paris Agreement requires the Senate's advice and consent) with David A. Wirth, The International and Domestic Law of Climate Change: A Binding International Agreement Without the Senate or Congress?, 39 Harv. Envtl. L. Rev. 515 (2015) (asserting that neither Senate advice and consent nor new congressional legislation are necessarily conditions precedent to the United States becoming a party to an international agreement related to emissions reduction and climate change).

See supra note 39.

See Made in the USA Found. v. United States, 242 F.3d 1300, 1319 (11th Cir. 2001), cert. denied, United Steelworkers v. United States, 534 U.S. 1039 (2001); Greater Tampa Chamber of Commerce v. Goldschmidt, 627 F.2d 258, 265–66 (D.C. Cir. 1980).

See Made in the USA Found., 242 F.3d at 1312–19. For background on the political question doctrine, see Cong. Research Serv., Overview of the Political Question Doctrine, Constitution Annotated, https://constitution.congress.gov/browse/essay/artIII-S2-C1-9-1/ALDE_00001283/ (last visited Jan. 25, 2023).

See, e.g., Inter-American Treaty of Reciprocal Assistance, Dec. 3, 1948, 62 Stat. 1681, 21 U.N.T.S. 77; North Atlantic Treaty, Apr. 4, 1949, 63 Stat. 2241, 34 U.N.T.S. 243; Security Treaty, Austl.-N.Z.-U.S., Sept. 1, 1951, 3 U.S.T. 3420; Mutual Defense Treaty, Phil.-U.S., Aug. 30, 1951, 3 U.S.T. 3947; Mutual Defense Treaty, S. Kor.-U.S., Oct. 1, 1953, 5 U.S.T. 2368; Southeast Asia Collective Defense Treaty, Sept. 8, 1954, 6 U.S.T. 81; Treaty of Mutual Cooperation and Security, Japan-U.S., Jan. 19, 1960, 11 U.S.T. 1632, (replacing Security Treaty, Japan-U.S., Sept. 8, 1951, 3 U.S.T. 3329).

See generally CRS Report 98-958, Extradition To and From the United States: Overview of the Law and Contemporary Treaties, by Michael John Garcia and Charles Doyle, at App. A (listing bilateral extradition treaties to which the United States is a party). Congress enacted statutes that permitted in certain circumstances the extradition of non-citizens to foreign countries even in the absence of a treaty, Antiterrorism and Effective Death Penalty Act of 1996, Pub. L. No. 104-132, § 443(a), 110 Stat. 1214, 1280, as well as the surrender of U.S. citizens to face prosecution before the International Tribunals for Rwanda and Yugoslavia, National Defense Authorization Act for Fiscal Year 1996, Pub. L. No. 104-106, § 1342, 110 Stat. 186, 486. The U.S. Court of Appeals for the Fifth Circuit upheld the legality of the latter statute and held that extradition may be effectuated pursuant to either a treaty or authorizing statute. Ntakirutimana v. Reno, 184 F.3d 419, 425 (5th Cir. 1999).

See, e.g., Convention on the Prevention and Punishment of the Crime of Genocide, adopted Dec. 9, 1948, 78 U.N.T.S. 277 (Agreement was not ratified by Congress until Nov. 5, 1988); International Covenant on Civil and Political Rights, adopted Dec. 19, 1966, S. Exec. Doc. No. E, 95-2, 999 U.N.T.S. 171 (Agreement was not ratified by Congress until June 8, 1992); Convention Against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment, adopted Dec. 10, 1984, S. Treaty Doc. No. 95-2, 1465 U.N.T.S. 85 (Agreement was not ratified by Congress until Oct. 21, 1994).

See, e.g., Treaty on the Non-Proliferation of Nuclear Weapons, opened for signature July 1, 1968, 21 U.S.T. 483; Treaty on the Limitation of Anti-Ballistic Missile Systems, U.S.-U.S.S.R., May 26, 1972, 23 U.S.T. 3435; Convention on the Prohibition of Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction, Jan. 13, 1993, S. Treaty Doc. No. 103-21, 1975 U.N.T.S. 3. But see 22 U.S.C. § 2573 (provision of 1961 Arms Control and Disarmament Act, as amended, generally barring acts that oblige the United States to limit forces or armaments in a "military significant manner" unless done pursuant to a treaty or further affirmative legislation by Congress); Interim Agreement on Certain Measures with Respect to the Limitation of Strategic Offensive Arms, U.S.-U.S.S.R., May 26, 1972, 23 U.S.T. 3462 (Strategic Arms Limitation Talks (SALT I) Interim Agreement, which was entered as a congressional-executive agreement, see Pub. L. No. 92-448, 86 Stat. 746, and was intended as a stop-gap, five-year measure while the parties negotiated a permanent agreement).

For a list of tax treaties to which the United States is a party, see United States Income Tax Treaties–A to Z, Internal Revenue Serv. (Apr. 28, 2022), https://www.irs.gov/businesses/international-businesses/united-states-income-tax-treaties-a-to-z.

See, e.g., Treaty Concerning the Canadian International Boundary, U.K.-U.S., Apr. 11, 1908, 35 Stat. 2003; Treaty to Resolve Pending Boundary Differences and Maintain the Rio Grande and Colorado River as the International Boundary, Mex.-U.S., Nov 23, 1970, 23 U.S.T. 371. The executive branch has regularly entered agreements to "provisionally" set boundaries pending ratification of a treaty intended to permanently resolve a boundary dispute. While some of these provisional agreements have been for a short duration, others have remained in effect for many years because of the lack of a ratified final agreement. For example, by way of a series of two-year executive agreements, the executive branch has continued to provisionally apply a proposed U.S.-Cuba maritime boundary agreement that was submitted to the Senate in 1978. See Sen. Exec. Doc. H, 96th Cong.

See, e.g., 137 Cong. Rec. 34348 (Nov. 23, 1991) (Treaty on Conventional Armed Forces in Europe); 143 Cong. Rec. 932 (Jan. 21, 1997) (Chemical Weapons Convention).

See 144 Cong. Rec. 7909 (May 4, 1998); 149 Cong. Rec. 10783 (May 8, 2003); 163 Cong. Rec. S2038 (daily ed. March 2018); 165 Cong. Rec. S5943 (daily ed. Oct. 22, 2019). A paragraph immediately following the consultation requirement states the following:

The Senate declares that no action or agreement other than a consensus decision by the full membership of NATO, approved by the national procedures of each NATO member, including, in the case of the United States, the requirements of Article II, section 2, clause 2 of the Constitution of the United States (relating to the advice and consent of the Senate to the making of treaties), will constitute a security commitment pursuant to the North Atlantic Treaty.

E.g., 144 Cong. Rec. 7909 (May 4, 1998).

Circular 175 initially referred to a 1955 Department of State circular that established a process for the coordination and approval of international agreements. These procedures, as modified, are now found in 22 C.F.R. Part 181 and Volume 11 of the Foreign Affairs Manual (FAM). See 11 FAM § 720.

11 FAM § 723.3.

S. Res. 536, 95th Cong. (1977).

11 FAM § 723.4(b)–(c).

Id. § 723.4(c).

See generally Memorandum from Robert E. Dalton on International Documents of Non-Legally Binding Character 1–5 (Mar. 18, 1994), https://2009-2017.state.gov/documents/organization/65728.pdf (discussing U.S. and international practice with respect to non-binding instruments); Duncan B. Hollis & Joshua J. Newcomer, "Political" Commitments and the Constitution, 49 Va. J. Int'l L. 507 (2009) (discussing the origins and constitutional implications of the practice of making political commitments); Curtis Bradley et al., The Rise of Nonbinding International Agreements: An Empirical, Comparative, and Normative Analysis, 90 Chi. L. Rev. (forthcoming 2023), https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4023641 (discussing increasing use of non-binding instruments for major international commitments).

E.g., Jean Galbraith & David Zaring, Soft Law as Foreign Relations Law, 99 Cornell L. Rev. 735 (2014); Curtis A. Bradley, International Law in the U.S. Legal System 96 (2d ed. 2015).

Conference on Security and Cooperation in Europe: Final Act, Aug. 1, 1975, 73 Dep't St. Bull. 323, Aug. 1, 1975 [hereinafter Helsinki Accords].

22 C.F.R. § 181.2(a)(1) ("In the absence of any provision in the arrangement with respect to governing law, it will be presumed to be governed by international law."). See also Hollis & Newcomer, supra note 91, at 525 ("To date, most (but not all) international lawyers favor a presumption of treaty making in lieu of creating political commitments.").

22 C.F.R. § 181.2(a)(1).

Id. § 181.2(a). See also Guidance on Non-Binding Documents, U.S. Dep't of State, https://2009-2017.state.gov/s/l/treaty/guidance/index.htm (last visited Jan. 12, 2023). Presidents sometimes unilaterally make temporary commitments known as modi vivendi arrangements, which are stopgap measures intended to guide the parties' conduct until they conclude a more permanent legal agreement. See generally William Hays Simpson, Use of Modi Vivendi in Settlement of International Disputes, 11 Rocky Mntn. L. Rev. 89 (1938); W. Michael Reisman, Unratified Treaties and Other Unperfected Acts in International Law: Constitutional Functions, 35 Vand. J. Transnational L. 729 (2002).

Compare, e.g., Press Briefing by Press Secretary Josh Earnest, White House (Jan. 29, 2015), https://obamawhitehouse.archives.gov/the-press-office/2015/01/29/press-briefing-press-secretary-josh-earnest-12915 ("[A] congressional vote on a nonbinding instrument is not required by law and could set an unhelpful precedent for other negotiations that result in other nonbinding instruments."); with S. Rep. No. 91-129 (1969) (Senate Committee on Foreign Relations report criticizing, among other things, the President's "national commitments" and unilateral pledges to other countries without congressional involvement).

S. Res. 85, 91st Cong. (1969).

Id. According to the committee report accompanying the National Commitments Resolution, the resolution arose from concern over the growing development of "constitutional imbalance" in matters of foreign relations, with Presidents frequently making significant foreign commitments on behalf of the United States without congressional action. S. Rep. No. 91-129, at 7 (1969). Among other things, the report criticized a practice it described as "commitment by accretion," by which a "sense of binding commitment arises out of a series of executive declarations, no one of which in itself would be thought of as constituting a binding obligation. Simply repeating something often enough with regard to our relations with some particular country, we come to support that our honor is involved in an engagement no less solemn than a duly ratified treaty." S. Rep. No. 91-129, at 26 (1969).

See, e.g., Orkin v. Taylor, 487 F.3d 734, 739 (9th Cir. 2007) ("'Sense of the Congress' provisions are precatory provisions, which do not in themselves create individual rights or, for that matter, any enforceable law."). For additional background on "sense of" provisions, see CRS Report 98-825, "Sense of" Resolutions and Provisions, by Christopher M. Davis.

See, e.g., Executive Agreements Review Act, H.R. 4438, 94th Cong. (1975) (proposing to establish legislative veto over executive agreements involving national commitments); Treaty Powers Resolution, S. Res. 24, 95th Cong. (1977) (proposing that it would not be in order for the Senate to consider any legislation authorizing funds to implement any international agreement that the Senate has found to constitute a treaty, unless the Senate has given its advice and consent to treaty ratification).

For background on the development of the transparency regime related to treaties and international agreements, see Treaties and Other International Agreements, supra note 11, at 209–12; Oona A. Hathaway et al., The Failed Transparency Regime for Executive Agreements: An Empirical and Normative Analysis, 134 Harv. L. Rev. 629, 645–56 (2020).

Several exceptions apply to the publication requirements in the pre-2023-NDAA version of 1 U.S.C. § 112a (2022). For example, publication is not required when the Secretary of State determines that public interest in the agreements is insufficient to justify publication. 1 U.S.C. § 112a(b)(2) (2022). The 2023 NDAA replaces these exceptions with a new list of agreements and instruments not subject to its transparency requirements. See infra "Congressional Reporting and Publication Requirements."

The Case-Zablocki Act authorizes the President to decline to transmit executive agreements to the Senate Foreign Relations Committee and the House Foreign Affairs Committee (then called the House Committee on International Relations) if, in the President's opinion, immediate public disclosure of the agreement would prejudice national security. See 1 U.S.C. § 112b(a) (2022).

The notification requirements in the Case-Zablocki Act were not interpreted to apply to every executive agreement. Legislative history suggests Congress "did not want to be inundated with trivia ... [but wished] to have transmitted all agreements of any significance." H.R. Rep. No. 92-301, 92nd Cong. (1972). Implementing State Department regulations set criteria for assessing when a compact constitutes an "international agreement" that must be reported under the Case-Zablocki Act. These regulations provide that "[m]inor or trivial undertakings, even if couched in legal language and form," are not considered to fall under the purview of the act's reporting requirements. 22 C.F.R. §181.2(a).

See Hathaway et al., supra note 102, at 657–91.

2023 NDAA, § 5947 (to be codified at 1 U.S.C. §§ 112a–112b).

The State Department's pre-2023-NDAA regulations on publication and reporting of international agreements do not apply to non-binding documents. See 22 C.F.R. § 181.2(a)(1). On at least one occasion, Congress enacted context-specific legislation requiring the executive branch to provide notification of any commitment, regardless of whether it was legally binding, so that Congress could give expedited consideration on whether to disapprove of the commitment. See Iran Nuclear Agreement Review Act of 2015, Pub. L. No. 114-17, § 2(h)(1), 129 Stat. 201, 211 (codified in 42 U.S.C. § 2160e(h)(1)).

2023 NDAA, § 5947(a)(1) (to be codified at 1 U.S.C. § 112b(k)(5)(A)).

Id.

Id. (to be codified at 1 U.S.C. § 112b(k)(5)(B)). Some observers argue that, because DOD concludes a high volume of non-binding instruments, the exemption for instruments based upon DOD, armed forces, and intelligence authorities will have the effect of excluding many non-binding instruments from the 2023 NDAA's disclosure requirements. See Curtis Bradley, Jack Goldsmith, Oona Hathaway, Congress Mandates Sweeping Transparency Reforms for International Agreements, Lawfare (Dec. 23, 2022), https://www.lawfareblog.com/congress-mandates-sweeping-transparency-reforms-international-agreements.

The 2023 NDAA defines international agreement as including any treaty that requires the Senate's advice and consent pursuant to Article II of the Constitution and "any other international agreement to which the United States is a part and that is not subject to the advice and consent of the Senate." 2023 NDAA § 5947(a)(1) (to be codified at 1 U.S.C. § 112b(k)(4)(A)–(B)).

Id. (to be codified at 1 U.S.C. § 112b(a)(1)).

Id. (to be codified at 1 U.S.C. § 112b(a)(1)(A)(ii) and (k)(7)(A)). If the text changes after signature or finalization, the executive branch must provide the updated text when the agreement or instrument enters into force or becomes operative. Id. (to be codified at 1 U.S.C. § 112b(a)(1)(B)(ii)). The list and text of international agreements may be submitted in classified and unclassified form. Id. (to be codified at 1 U.S.C. § 112b(a)(2)).

Id. (to be codified at 1 U.S.C. § 112b(a)(1)(A)(iii)). If multiple authorities are relied upon, the executive branch must cite all authorities.

Id. When no specific article, section, or subsection is available, the citation must be "as specific as possible." Id.

2023 NDAA § 5947(a)(1) (to be codified at 1 U.S.C. § 112b(a)(1)(A)(iii)).

Id. (to be codified at 1 U.S.C. § 112b(a)(1)(B)(iii)).

Id. (to be codified at 1 U.S.C. § 112b(b)(1)–(2)). The State Department must make available upon request any international agreement or qualifying non-binding instrument that is in its possession but not published. Id. § 5947(b) (to be codified at 1 U.S.C. § 112a(b)).

Id. (to be codified at 1 U.S.C. § 112b(b)(3).

Id. (to be codified at 1 U.S.C. § 112b(b)(3)(A)–(E)).

Id. (to be codified at 1 U.S.C. § 112b(c)).

2023 NDAA § 5947(a)(1) (to be codified at 1 U.S.C. § 112b(c)).

Id. (to be codified at 1 U.S.C. § 112b(d)(1)–(3)). Agencies must also provide implementing material on an ongoing basis as necessary to fulfil congressional reporting requirements. See id. (to be codified at 1 U.S.C. § 112b(d)(4)).

Id. (to be codified at 1 U.S.C. § 112b(g)).

Id. (to be codified at 1 U.S.C. § 112b(e)).

Id. (to be codified at 1 U.S.C. § 112b(f)).

Id. (to be codified at 1 U.S.C. § 112b(j)).

2023 NDAA § 5947(a)(1) (to be codified at 1 U.S.C. § 112b(h)(1)).

Id. § 5947(a)(4) (to be codified at 1 U.S.C. § 112b note).

Id. § 5947(a)(6)(A) (to be codified at 1 U.S.C. § 112b note).

Id. § 5957(a)(6)(B) (to be codified at 1 U.S.C. § 112b note).

See, e.g., Medellín v. Texas, 552 U.S. 491, 505 n.2 (2008) ("What we mean by 'self-executing' is that the treaty has automatic domestic effect as federal law upon ratification."); Cook v. United States, 288 U.S. 102, 119 (1933) ("For in a strict sense the [t]reaty was self-executing, in that no legislation was necessary to authorize executive action pursuant to its provisions."); Foster v. Neilson, 27 U.S. (2 Pet.) 253, 254 (1829) (Marshall, C.J.) (describing a treaty as "equivalent to an act of the legislature" when it "operates of itself without the aid of any legislative provision"), overruled on other grounds by United States v. Percheman, 32 U.S. (7 Pet.) 51 (1833); CLMS Mgmt. Servs. Ltd. P'ship v. Amwins Brokerage of Ga., LLC, 8 F.4th 1007, 1013 (9th Cir. 2021) (provision mandating that domestic courts "shall" enforce arbitration agreements was self-executing), cert. denied, 142 S. Ct. 862 (2022).

See Medellín, 552 U.S. at 505 n.2 ("[A] 'non-self-executing' treaty does not by itself give rise to domestically enforceable federal law. Whether such a treaty has domestic effect depends upon implementing legislation passed by Congress."

E.g., Id. at 505 ("[W]hile treaties may comprise international commitments, they are not domestic law unless Congress has either enacted implementing statutes or the treaty itself conveys an intention that it be 'self-executing' and is ratified on these terms.") (citations, internal quotation marks, and alteration omitted); Whitney v. Robertson, 124 U.S. 190, 194 (1888) ("When the [treaty] stipulations are not self-executing, they can only be enforced pursuant to legislation to carry them into effect, and such legislation is as much subject to modification and repeal by [C]ongress as legislation upon any other subject.").

See, e.g., Medellín, 552 U.S. at 507–08; Foster, 27 U.S. (2 Pet.) at 254.

See, e.g., Sosa v. Alvarez-Machain, 542 U.S. 692, 735 (2004).

See, e.g., Medellín, 552 U.S. at 503–04.

See, e.g., Fourth Restatement, supra note 12, § 310(3) & cmt. c. See also 5 Annals of Cong. 771 (1796) (resolution passed by the House of Representatives stating that "when a treaty stipulates regulations on any of the subjects submitted by the Constitution to the power of Congress, it must depend for its execution as to such stipulations on a law or laws to be passed by Congress").

See Edwards v. Carter, 580 F.2d 1055, 1058 (D.C. Cir. 1978) (per curiam) ("[E]xpenditure of funds by the United States cannot be accomplished by self-executing treaty; implementing legislation appropriating such funds is indispensable."), cert. denied, 436 U.S. 907 (1978); The Over the Top, 5 F.2d 838, 845 (D. Conn. 1925) ("All treaties requiring payments of money have been followed by acts of Congress appropriating the amount. The treaties were the supreme law of the land, but they were ineffective to draw a dollar from the treasury."); Turner v. Am. Baptist Missionary Union, 24 F. Cas. 344, 345 (C.C.D. Mich. 1852) ("[M]oney cannot be appropriated by the treaty-making power. This results from the limitations of our government.").

See Hopson v. Kreps, 622 F.2d 1375, 1380 (9th Cir. 1980) ("Treaty regulations that penalize individuals ... require domestic legislation before they are given any effect."); United States v. Postal, 589 F.2d 862, 877 (5th Cir. 1979) (noting that constitutional restrictions on the use of a self-executing treaty to withdraw money from the treasury would also "be the case with respect to criminal sanctions"), cert. denied, 444 U.S. 832 (1979).

See Edwards, 580 F.2d at 1058 ("[T]he constitutional mandate that 'all Bills for raising Revenue shall originate in the House of Representatives,' ... appears, by reason of the restrictive language used, to prohibit the use of the treaty power to impose taxes.... ") (quoting U.S. Const. art. I, § 7, cl. 1); Swearingen v. United States, 565 F. Supp. 1019, 1022 (D. Colo. 1983).

U.S. Const. art. VI, cl. 2 ("[A]ll Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land.... ").

See, e.g., The Over the Top, 5 F.2d at 845 ("The treaties were the supreme law of the land, but they were ineffective to draw a dollar from the treasury."); Fourth Restatement, supra note 12, § 310 reporters' n.12 ("[T]here is no clear reason at present to conclude that non-self-executing provisions are, as a general matter, less than supreme law."); Brian Finucane, Presidential War Powers, the Take Care Clause, and Article 2(4) of the U.N. Charter, 105 Cornell L. Rev. 1809, 1828 (2020) (arguing that "treaties generally, and the U.N. Charter in particular, are 'Laws'" in the constitutional sense).

See, e.g., Auguste v. Ridge, 395 F.3d 123, 133 (3d Cir. 2005) ("Treaties that are not self-executing do not create judicially-enforceable rights unless they are first given effect by implementing legislation."); Bradley, supra note 92, at 44 (summarizing the debate of the domestic status of non-self-executing treaties).

ITC Ltd. v. Punchgini, Inc., 482 F.3d 135, 162 n.21 (2d Cir. 2007) ("Non-self-executing treaties do not become effective as domestic law until implementing legislation is enacted."), certified question answered, 880 N.E.2d 852 (N.Y. 2007); Renkel v. United States, 456 F.3d 640, 643 (6th Cir. 2006) ("[N]on-self-executing' treaties do require domestic legislation to have the force of law."); Authority of the Federal Bureau of Investigation To Override International Law in Extraterritorial Law Enforcement Activities, 13 Op. O.L.C. 163, 178–79 (1989) ("[U]nexecuted treaties ... are not legally binding on the political branches.").

See, e.g., David Sloss, The Domestication of International Human Rights: Non-Self-Executing Declarations and Human Rights Treaties, 24 Yale J. Int'l L. 129, 197–216 (1999); Carlos Manuel Vazquez, Treaty-Based Rights and Remedies of Individuals, 92 Colum. L. Rev. 1082, 1143–44 (1992).

See, e.g., Medellín v. Texas, 552 U.S. 491, 504–06 (2008) (discussing the distinction between the binding effect of treaties under international law versus domestic law).

See Head Money Cases, 112 U.S. 580, 598 (1884) ("[A treaty] depends for the enforcement of its provisions on the interest and the honor of the governments which are parties to it."); Fourth Restatement, supra note 12, §§ 310(3), 110 cmt. c ("It is ordinarily up to each nation to decide how to implement domestically its international obligations.").

See Medellín, 552 U.S. at 522–23.

See Third Restatement, supra note 1, § 111, cmt. h.

See Henkin, supra note 22, at 204. See also supra "Self-Executing vs. Non-Self-Executing Agreements" (discussing Congress's role in implementing non-self-executing treaties).

Whereas Alexander Hamilton argued that the House of Representatives was obligated to appropriate funds for the Jay Treaty, supra note 37, James Madison, then a Member of the House of Representatives, and others disagreed. Compare Enclosure to Letter from Alexander Hamilton, to George Washington (Mar. 29, 1796), in Papers of Alexander Hamilton 98 (Harold C. Syrett ed., 1974) ("[T]he house of representatives have no moral power to refuse the execution of a treaty, which is not contrary to the constitution, because it pledges the public faith, and have no legal power to refuse its execution because it is a law—until at least it ceases to be a law by a regular act of revocation of the competent authority."), and 5 Annals of Cong. 493–94 (1796) (statement of Rep. Madison) ("[T]his House, in its Legislative capacity, must exercise its reason; it must deliberate; for deliberation is implied in legislation. If it must carry all Treaties into effect, ... it would be the mere instrument of the will of another department, and would have no will of its own."); with id. at 771 (proposed resolution of Rep. Blount) ("[W]hen a Treaty stipulates regulations on any of the subjects submitted by the Constitution to the power of Congress, it must depend, for its execution, as to such stipulations, on a law or laws to be passed by Congress. And it is the Constitutional right and duty of the House of Representatives, in all such cases, to deliberate on the expediency or inexpediency of carrying such Treaty into effect. . . .").

See Henkin, supra note 22, at 205.

252 U.S. 416 (1920).

See Migratory Bird Treaty Act, Pub. L. No. 65-186, 40 Stat. 755 (1918); Convention for the Protection of Migratory Birds, art. VIII, Gr. Brit.-U.S., Aug. 16, 1916, 39 Stat. 1702.

U.S. Const. amend. X (The Tenth Amendment provides "The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."). For background on the Tenth Amendment, see Cong. Research Serv., Overview of Tenth Amendment, Rights Reserved to the States and the People, Constitution Annotated, https://constitution.congress.gov/browse/essay/amdt10-1/ALDE_00013619/ (last visited Jan. 12, 2023).

United States v. McCullagh, 221 F. 288, 295–96 (D. Kan. 1915); United States v. Shauver, 214 F. 154, 160 (E.D. Ark. 1914).

See Missouri v. Holland, 252 U.S. 416, 433 (1920).

See id. at 433–34 (concluding that the "treaty in question does not contravene any prohibitory words to be found in the Constitution" and is not "forbidden by some invisible radiation from the general terms of the Tenth Amendment").

See U.S. Const. art. I, § 8, cl. 18.

See Holland, 252 U.S. at 432 ("If the treaty is valid there can be no dispute about the validity of the statute under Article 1, Section 8, as a necessary and proper means to execute the powers of the Government."). Accord Neely v. Henkel, 180 U.S. 109, 121 (1901) ("The power of Congress to make all laws necessary and proper ... includes the power to enact such legislation as is appropriate to give efficacy to any stipulations which it is competent for the President by and with the advice and consent of the Senate to insert in a treaty with a foreign power.").

See Reid v. Covert, 354 U.S. 1, 16–17 (1957) (plurality opinion) (responding to dicta in Holland by clarifying that the treaty power is subject to certain constitutional constraints); Bond v. United States, 572 U.S. 844, 873 (2014) (Scalia, J., concurring in the judgment) (joined by Thomas, J.) (describing Holland's interpretation of the Necessary and Proper Clause as consisting of an "unreasoned and citation-less sentence" that is unsupported by the Constitution's text or structure); United States v. Rife, 33 F.4th 838, 842 n.1 (6th Cir. 2022) ("Holland itself might rest on shaky ground"), cert. denied, 214 L. Ed. 2d 172, 143 S. Ct. 356 (2022); Nicholas Quinn Rosenkranz, Executing the Treaty Power, 118 Harv. L. Rev. 1867, 1868 (2005) (arguing that Holland's interpretation of the Necessary and Proper Clause "is wrong and the case should be overturned"). In the 1950s, there was an effort, led by Senator John Bricker of Ohio, to limit the scope of the treaty power as described in Holland through a constitutional amendment. One version of the proposed amendment, which became known as the "Bricker Amendment," would have provided that a "treaty shall become effective as internal law in the United States only through legislation which would be valid in the absence of a treaty." See S. Comm. on the Judiciary, 83d Cong., Proposals to Amend the Treaty-Making Provisions of the Constitution: Views of Deans and Professors of Law 3 (Comm. Print 1953). No version of the Bricker Amendment was ever adopted.

Bradley, supra note 92, at 86.

See United States v. Lara, 541 U.S. 193, 201 (2004) ("[A]s Justice Holmes pointed out, treaties made pursuant to [the treaty] power can authorize Congress to deal with 'matters' with which otherwise 'Congress could not deal.'") (quoting Holland, 252 U.S. at 433); Reid, 354 U.S. at 18 (plurality opinion) ("To the extent that the United States can validly make treaties, the people and the States have delegated their power to the National Government and the Tenth Amendment is no barrier.").

Bond, 572 U.S. at 844.

Bond, 572 U.S. at 861.

Chemical Weapons Convention Implementation Act of 1998, Pub. L. No. 105-277, div. I, tit. II, § 201(a), 112 Stat. 2681, 2681–866 (codified in 18 U.S.C. §§ 229–229f); Convention on the Prohibition of the Development, Production, Stockpiling, and Use of Chemical Weapons and on Their Destruction art. 1, Jan. 13, 1993, 1974 U.N.T.S. 317.

Bond, 572 U.S. at 863.

See id. at 854–55. Justice Scalia and Justice Thomas criticized Holland and argued that the Supreme Court should depart from its interpretation of congressional power to enact legislation that is necessary and proper to implement treaties. See id. at 880–81 (Scalia, J., concurring in the judgment) (joined by Thomas, J.).

See id. at 858–60.

Id. at 859–60.

See id. at 858–60.

Accord William S. Dodge, Bond v. United States and Congress's Role in Implementing Treaties, 108 AJIL Unbound 86, 87 (2015) ("The central holding of Bond is that statutes implementing treaties are not exceptions to the rules of statutory interpretation that the Supreme Court has developed to protect federalism.").

See Am. Ins. Ass'n v. Garamendi, 539 U.S. 396, 416–17 & n.9 (2003) (stating that the power of a treaty to preempt state law is "[s]ubject ... to the Constitution's guarantees of individual rights"); Boos v. Barry, 485 U.S. 312, 324 (1988) ("It is well established that 'no agreement with a foreign nation can confer power on the Congress, or on any other branch of Government, which is free from the restraints of the Constitution.'") (quoting Reid v. Covert, 354 U.S. 1, 16 (1957) (plurality opinion)); Asakura v. City of Seattle, 265 U.S. 332, 343 (1924) ("The treaty-making power of the United States ... does not extend 'so far as to authorize what the Constitution forbids.... '") (quoting De Geofroy v. Riggs, 133 U.S. 258, 267 (1890)); Doe v. Braden, 57 U.S. (16 How.) 635, 657 (1854) ("The treaty is therefore a law made by the proper authority, and the courts of justice have no right to annul or disregard any of its provisions, unless they violate the Constitution of the United States.").

See Whitney v. Robertson, 124 U.S. 190, 194 (1888) ("By the constitution, a treaty is placed on the same footing, and made of like obligation, with an act of legislation. Both are declared by that instrument to be the supreme law of the land, and no superior efficacy is given to either over the other."); Ware v. Hylton, 3 U.S. (3 Dall.) 199, 237 (1796) ("[L]aws of any of the States, contrary to a treaty, shall be disregarded.").

The Supreme Court has not directly addressed whether self-execution analysis applies to executive agreements, but lower courts have presumed that it does. See, e.g., Islamic Republic of Iran v. Boeing Co., 771 F.2d 1279, 1283 (9th Cir. 1985); United States v. Sum of $70,990,605, 234 F. Supp. 3d 212, 233 (D.D.C. 2017); Beeler v. Berryhill, 381 F. Supp. 3d 991, 998 (S.D. Ind. 2019), aff'd sub nom. Beeler v. Saul, 977 F.3d 577 (7th Cir. 2020).

See Am. Ins. Ass'n v. Garamendi, 539 U.S. 396, 415 (2003); United States v. Pink, 315 U.S. 203, 229 (1942); United States v. Belmont, 301 U.S. 324, 330 (1937).

See, e.g., Validity of Congressional-Executive Agreements that Substantially Modify the United States' Obligations Under an Existing Treaty, 20 Op. O.L.C. 389, 397–98 (1996); Bradley, supra note 92, at 78–82.

See United States v. Guy W. Capps, Inc., 204 F.2d 655, 660–61 (4th Cir. 1953); Swearingen v. United States, 565 F. Supp. 1019, 1020–21 (D. Colo. 1983).

See Pink, 315 U.S. at 230 ("'All [c]onstitutional acts of power, whether in the executive or in the judicial department, have as much legal validity and obligation as if they proceeded from the legislature.... '") (quoting The Federalist No. 64 (John Jay)); Dames & Moore v. Regan, 453 U.S. 654 (1981) (upholding sole executive agreement concerning the handling of Iranian assets in the United States despite the existence of a potentially conflicting statute given Congress's historical acquiescence to these types of agreements).

Whitney v. Robertson, 124 U.S. 190, 195 (1888).

See, e.g., Cook v. United States, 288 U.S. 102, 118–19 (1933); Whitney, 124 U.S. at 194–95; The Cherokee Tobacco, 78 U.S. (11 Wall.) 616, 621 (1870).

Some courts have disagreed on the domestic legal effect of a non-self-executing treaty following the enactment of implementing legislation. Compare Stephens v. Am. Int'l Ins. Co., 66 F.3d 41, 45 (2d Cir. 1995) (stating that legislation implementing non-self-executing agreement informed analysis as to whether state law was preempted, rather than the agreement itself) with Safety Nat'l Cas. Corp. v. Certain Underwriters at Lloyd's, London, 587 F.3d 714, 725–27 (5th Cir. 2009) (en banc) (interpreting text of international agreement, rather than its implementing legislation, to supersede state law), cert. denied, La. Safety Ass'n of Timbermen—Self Insurers Fund v. Certain Underwriters at Lloyd's, London, 562 U.S. 827 (2010).

Medellín v. Texas, 552 U.S. 491, 525–26 (2008).

Id. at 525–26 (holding that a presidential memorandum ordering a U.S. state court to give effect to a non-self-executing treaty requirement did not constitute federal law preempting the state's procedural default rules).

See Sanchez-Llamas v. Oregon, 548 U.S. 331, 353–54 (2006) ("If treaties are to be given effect as federal law under our legal system, determining their meaning as a matter of federal law 'is emphatically the province and duty of the judicial department.... '") (quoting Marbury v. Madison, 5 U.S. (1 Cranch) 137, 177 (1803)).

See, e.g., BG Grp., PLC v. Republic of Arg., 572 U.S. 25, 37 (2014); Lozano v. Montoya Alvarez, 572 U.S. 1, 11 (2014); Sumitomo Shoji Am., Inc. v. Avagliano, 457 U.S. 176, 183 (1982); Wright v. Henkel, 190 U.S. 40, 57 (1903).

Water Splash, Inc. v. Menon, 581 U.S. 271, 277–78 (2017) (quoting Volkswagenwerk Aktiengesellschaft v. Schlunk, 486 U.S. 694, 699 (1988)); Société Nationale Industrielle Aerospatiale v. U.S. Dist. Ct. for S. Dist. of Iowa, 482 U.S. 522, 534 (1987); Air France v. Saks, 470 U.S. 392, 397 (1985).

See, e.g., Water Splash, 581 U.S. at 279–81; Schlunk, 486 U.S. at 699. In one case, the Supreme Court changed its conclusion about the self-executing effect of a provision in an 1819 treaty with Spain after analyzing an authenticated Spanish-language version of the text. Compare Foster v. Neilson, 27 U.S. (2 Pet.) 253, 314–15 (1829) (construing English language version of 1819 treaty between the United States and Spain and deeming a provision stating that certain land grants "shall be ratified and confirmed" to be non-self-executing) (emphasis added), with United States v. Percheman, 32 U.S. (7 Pet.) 51, 88–89 (1833) (concluding that the land grant provision at issue was self-executing after interpreting the Spanish language version, which was translated to state that the land grants "shall remain ratified and confirmed") (emphasis added).

See, e.g., Abbott v. Abbott, 560 U.S. 1, 20 (2010); Sanchez-Llamas, 548 U.S. at 347; Société Nationale Industrielle Aerospatiale, 482 U.S. at 530; E. Airlines, Inc. v. Floyd, 499 U.S. 530, 552 (1991).

See, e.g., Water Splash, 581 U.S. at 279–81; Medellín, 552 U.S. at 507; Air France, 470 U.S. at 400; Schlunk, 486 U.S. at 700.

See, e.g., 581 U.S. at 279–83; Abbott, 560 U.S. at 16; Lozano, 572 U.S. 1, 11–13 (2014); Air France, 470 U.S. at 404.

See, e.g., Medellín, 552 U.S. at 507; TWA v. Franklin Mint Corp., 466 U.S. 243, 259 (1984).

See, e.g., Chan v. Korean Air Lines, Ltd., 490 U.S. 122, 134 (1989).

See, e.g., Relevance of Senate Ratification History to Treaty Interpretation, 11 Op. O.LC. 28, 30 (1987) ("[T]he President is responsible for enforcing and executing international agreements, a responsibility that necessarily 'involves also the obligation and authority to interpret what the treaty requires.'") (quoting Louis Henkin, Foreign Affairs and the Constitution 167 (1st ed. 1972)); Fourth Restatement, supra note 12, § 306 cmt. g ("Execution of a treaty requires interpretation, and the President often determines what a treaty means in the first instance.... ").

See 229 U.S. 447, 475 (1913).

See Fourth Restatement, supra note 12, § 306 cmt. g & reporters' n.10 (discussing the executive branch's unique access to information related to treaty interpretation). Accord Sumitomo Shoji Am., Inc. v. Avagliano, 457 U.S. 176, 184–85 (1982) (giving deference to the State Department's interpretation of a treaty because it is the agency "charged with [the treaty's] negotiation and enforcement").

See Water Splash, Inc. v. Menon, 581 U.S. 271, 281 (2017) (quoting Abbott v. Abbott, 560 U.S. 1, 15 (2010)); Medellín, 552 U.S. at 513; Avagliano, 457 U.S. at 184–85; Kolovrat v. Oregon, 366 U.S. 187, 194 (1961).

See BG Grp., PLC v. Republic of Arg., 572 U.S. 25, 37 (2014) (construing a dispute resolution provision in an investment treaty between the United Kingdom and Argentina and concluding "[w]e do not accept the Solicitor General's view as applied to the treaty before us"); Hamdan v. Rumsfeld, 548 U.S. 557, 629–30 (2006) (declining to adopt the executive branch's interpretation of Common Article 3 of the 1949 Geneva Conventions).

See Henkin, supra note 22, at 206 ("Congress, too, has occasion to interpret a treaty when it considers enacting implementing legislation, or other legislation to which the treaty might be relevant.").

See United States v. Stuart, 489 U.S. 353, 365–68 (1989) (considering, but deeming inconclusive, a treaty's ratification history); Société Nationale Industrielle Aerospatiale v. U.S. Dist. Ct. for S. Dist. of Iowa, 482 U.S. 522, 531 (1987) (discussing Secretary of State's analysis of the purposes of a treaty that was provided to the Senate).

See The Diamond Rings v. United States, 183 U.S. 176, 180 (1901) (declining to give legal weight to a Senate resolution attempting to clarify a ratified treaty because the "meaning of the treaty cannot be controlled by subsequent explanations of some of those who may have voted to ratify it").

For example, the Senate has frequently conditioned its advice and consent to treaties on what has become known as the "Byrd-Biden condition," which provides that "the United States shall interpret the Treaty in accordance with the common understanding of the Treaty shared by the President and the Senate at the time the Senate gave its advice and consent to ratification.... " 134 Cong. Rec. 12849 (1988). See also Treaties and Other International Agreements, supra note 11, at 129–30 (providing a history of the Byrd-Biden condition and examples of its use).

See The Diamond Rings, 183 U.S. at 180.

See, e.g., Goldwater v. Carter, 444 U.S. 996, 1003 (1979) (plurality opinion) ("[W]hile the Constitution is express as to the manner in which the Senate shall participate in the ratification of a treaty, it is silent as to that body's participation in the abrogation of a treaty."); Henkin, supra note 22, at 211 ("[T]he Constitution tells us only who can make treaties for the United States; it does not tell us who can unmake them.").

See supra "Executive Agreements."

For more detailed analysis of international and domestic legal principles related to withdrawal from international agreements, see CRS Report R44761, supra note 69.

See Bradley & Goldsmith, supra note 11, at 1225; Treaties and Other International Agreements, supra note 11, at 172; Third Restatement, supra note 1, § 339 reporters' n.2.

See Bradley & Goldsmith, supra note 11, at 1225 ("Presidents clearly have the authority to terminate sole executive agreements and political commitments, since those agreements are made by Presidents based on their own constitutional authority."); Third Restatement, supra note 1, § 339 reporters' n.2 ("No one has questioned the President's authority to terminate sole executive agreements.").

See, e.g., Julian Ku, President Rubio/Walker/Trump/Whomever Can Indeed Terminate the Iran Deal on "Day One," Opinio Juris (Sept. 10, 2015), https://tinyurl.com/ydfodbbo (arguing that, because the JCPOA is a non-binding political commitment, the President can unilaterally terminate the arrangement); Ryan Harrington, A Remedy for Congressional Exclusion from Contemporary International Agreement Making, 118 W. Va. L. Rev. 1211, 1226 (2016) ("A political commitment also provides the executive branch with the ability to terminate the agreement unilaterally or to deviate from it without consequences.").

See Third Restatement, supra note 1, § 339 cmt. a; Treaties and Other International Agreements, supra note 11, at 174, 208; Michael J. Glennon, Can the President Do No Wrong?, 80 Am. J. Int'l L. 923, 926 (1986). See also Hathaway, supra note 41, at 1362 n.268 ("The President may withdraw from ... a congressional-executive agreement unilaterally unless Congress has expressly limited the President's power to withdraw through ... authorizing legislation.... ").

See Third Restatement, supra note 1, § 339 cmt. a.

Act of June 14, 1948, Pub. L. No. 80-643, 62 Stat. 441, 442. In 2020, the Trump Administration announced its intent to withdraw from the World Health Organization but stated that its withdrawal would become effective one year later, consistent with the statutory notification requirement. See Briefing on the U.S. Government's Next Steps With Regard to Withdrawal From the World Health Organization, U.S. Dep't of State (Sept. 2, 2020), https://2017-2021.state.gov/briefing-with-nerissa-cook-deputy-assistant-secretary-of-state-bureau-of-international-organization-affairs-garrett-grigsby-director-of-the-office-of-global-affairs-department-of-health-and-human/index.html (statement of Nerissa J. Cook, Deputy Assistant Sec'y). The Biden Administration rescinded the withdrawal notice before it became effective. See Letter from Joseph R. Biden, Jr., President, White House, to His Excellency António Guterres, Sec'y-Gen., United Nations (Jan. 20, 2021), https://www.whitehouse.gov/briefing-room/statements-releases/2021/01/20/letter-his-excellency-antonio-guterres/.

Pub. L. No. 99-440, §§ 306(b)(1), 313, 100 Stat. 1086, 1100 ("The Secretary of State shall terminate the Agreement Between the Government of the United States of America and the Government of the Union of South Africa Relating to Air Services Between their Respective Territories.... "), repealed by South African Democratic Transition Support Act of 1993, Pub. L. No. 103-149, § 4, 107 Stat. 1503, 1505. The Reagan Administration complied and provided the requisite notice of termination. See South African Airways v. Dole, 817 F.2d 119, 121 (D.C. Cir. 1987), cert denied, 484 U.S. 896 (1987).

See Pub. L. No. 82-50, § 5, 65 Stat. 72, 73. The Truman Administration relied on this law in terminating certain congressional-executive agreements with the Soviet Union and several Soviet satellite countries. Office of the Historian, Foreign Relations of the United States, 1951, Europe: Political and Economic Developments, Volume IV, Part 2, U.S. Dep't of State, https://history.state.gov/historicaldocuments/frus1951v04p2/d169.

Authority to Withdraw from the North American Free Trade Agreement, 42 Op. O.L.C. __, slip op. at 1 (Oct. 17, 2018), https://www.justice.gov/olc/file/2018-10-17-nafta-wd/download [hereinafter OLC NAFTA Opinion].

Id.

See Julian Ku & John Yoo, Trump Might be Stuck with NAFTA, L.A. Times (Nov. 29, 2016), https://www.latimes.com/opinion/op-ed/la-oe-yoo-ku-trump-nafta-20161129-story.html (arguing that Congress's Commerce Clause authority bars the President from terminating NAFTA without congressional authorization); Joel P. Trachtman, Trump Can't Withdraw from NAFTA Without a 'Yes' from Congress, Hill (Aug. 16, 2017), https://tinyurl.com/y9byuyed ("If the president, acting alone, were to terminate U.S. participation in NAFTA, he would be imposing regulation on commerce, without congressional participation. This would be an unconstitutional usurpation of the powers granted to Congress.").

United States-Mexico-Canada Agreement Implementation Act, Pub. L. No. 116-113, § 101, 134 Stat. 11, 14–15 (2020).

See Treaties and Other International Agreements, supra note 11, at 208 ("[T]he President's authority to terminate executive agreements ... has not been seriously questioned in the past."); Curtis A. Bradley, Exiting Congressional-Executive Agreements, 67 Duke L.J. 1615, 1639 (2018) ("Congress has not indicated that it views congressional-executive agreements as special with respect to the issue of presidential termination authority.").

See notes 223, 243–244, 246 (citing academic literature and litigation involving Members of Congress challenging the President's unilateral treaty withdrawal power).

See, e.g., Barry M. Goldwater, Treaty Termination is a Shared Power, 65 A.B.A. J. 198, 199–200 (1979).

See, e.g., Clinton v. City of New York, 524 U.S. 417, 438 (1998) ("There is no provision in the Constitution that authorizes the President to enact, to amend, or to repeal statutes."); INS v. Chadha, 462 U.S. 919, 954 (1983) ("[R]epeal of statutes, no less than enactment, must conform with Art. I.").

See, e.g., David Gray Adler, The Constitution and the Termination of Treaties 89–110 (1986).

Compare U.S. Const. art. I, § 7, cl. 2 (authorizing congressional vetoes over legislation), with id. art. II, § 2, cl. 2 (requiring advice and consent for treaties).

See, e.g., Adler, supra note 225, at 94.

Act of July 7, 1798, ch. 68, 1 Stat. 578.

See Thomas Jefferson, A Manual of Parliamentary Practice § 51 (Samuel Harrison Smith ed., 1801) ("Treaties being declared, equally with the laws of the U[nited] States, to be the supreme law of the land, it is understood that an act of the legislature alone can declare them infringed and rescinded. This was accordingly the process adopted in the case of France in 1798.").

See, e.g., Curtis A. Bradley, Treaty Termination and Historical Gloss, 92 Tex. L. Rev. 773, 789 (2014); Treaties and Other International Agreements, supra note 11, at 207.

See S. Rep. No. 34-97, at 5 (1856) (Senate Foreign Relations Committee describing the 1798 treaty abrogation statute as a "rightful exercise of the war power, without viewing it in any manner as a precedent establishing in Congress alone, and under any circumstances, the power to annul a treaty."). Cf. Bas v. Tingy, 4 U.S. (4 Dall.) 37, 40 (1800) (opinion of Washington, J.) (treating the 1798 statute as one in a bundle of congressional acts declaring a limited "public war" on the French Republic).

For analysis of 19th-century understanding and practice related to treaty termination, see Bradley, supra note 230, at 788–801; Crandall, supra note 27, at 423–66.

See, e.g., Joint Resolution of April 27, 1846 Concerning the Oregon Territory, 9 Stat. 109; Joint Resolution of June 17, 1874, 18 Stat. 287.

See, e.g., Joint Resolution of Jan. 18, 1865, 13 Stat. 566; Joint Resolution of Mar. 3, 1883, 22 Stat. 641.

See, e.g., Franklin Pierce, Third Annual Message (Dec. 31, 1855), in 7 A Compilation of the Messages and Papers of the Presidents 2860, 2867 (James D. Richardson ed., 1897).

For example, after Congress enacted a joint resolution calling for the termination of the Oregon Territory Treaty, supra note 233, the Secretary of State informed the U.S. ambassador to Great Britain that "Congress have spoken their will upon the subject, in their joint resolution; and to this it is his (the President's) and your duty to conform." S. Doc. 29-489, at 15 (1846). As required by the Joint Resolution of January 18, 1865, supra note 234, the Andrew Johnson Administration terminated an 1854 treaty with Great Britain concerning trade with Canada. Letter from William H. Seward, U.S. Sec'y of State, to Charles Francis Adams, Minister to the U.K. (Jan. 18, 1865), in Papers Relating to Foreign Affairs, pt. 1, at 93 (1866).

See, e.g., Joint Resolution to Terminate the Treaty of 1817 Regulating the Naval Force on the Lakes, 13 Stat. 568; Joint Resolution of Dec. 21, 1911, 37 Stat. 627.

See Bradley, supra note 230, at 807–09.

See, e.g., Comprehensive Anti-Apartheid Act of 1986, Pub. L. No. 99-440, § 313, 100 Stat. 1086, 1104, repealed by South African Democratic Transition Support Act of 1993, Pub. L. No. 103-149, § 4, 107 Stat. 1503, 1505; Magnuson-Stevens Fishery Conservation and Management Act, Pub. L. No. 94-265, § 202(b), 90 Stat. 331, 339–40 (1976) (codified in 16 U.S.C. § 1822).

See Bradley, supra note 230, at 807–15.

Mutual Defense Treaty, Taiwan-U.S., Dec. 2, 1954, 6 U.S.T. 433.

For background on Goldwater v. Carter, see Victoria Marie Kraft, The U.S. Constitution and Foreign Policy: Terminating the Taiwan Treaty 1–52 (1991).

444 U.S. 996 (1979).

See id. at 996 (vacating with instructions to dismiss with no majority opinion).

See id. at 1002–05 (Rehnquist, J., concurring) (joined by Stewart, Stevens, JJ. & Burger, C.J.). Justice Powell also voted for dismissal but did so based on the grounds that the case was not ripe for judicial review until the Senate passed a resolution disapproving of the President's termination. See id. at 998 (Powell, J., concurring). Justice Brennan would have held that President Carter possessed the power to terminate the Mutual Defense Treaty with Taiwan, but his opinion centered on the President's power over recognition of foreign governments and not because he believed the President possessed a general, constitutional power to terminate treaties. See id. at 1006–07 (Brennan, J., dissenting).

In 1986, a federal district court dismissed a suit brought by a group of private plaintiffs seeking to prevent President Reagan from unilaterally terminating a Treaty of Friendship, Commerce, and Navigation with Nicaragua. See Beacon Prods. Corp. v. Reagan, 633 F. Supp. 1191, 1198–99 (D. Mass. 1986), aff'd on other grounds, 814 F.2d 1 (1st Cir. 1987).

In 2002, the U.S. District Court for the District of Columbia dismissed as nonjusticiable a challenge brought by 32 Members of Congress to President George W. Bush's termination of the Anti-Ballistic Missile Treaty with Russia. See Kucinich v. Bush, 236 F. Supp. 2d 1, 14–17 (D.D.C. 2002).

Congressionally Mandated Notice Period for Withdrawing from the Open Skies Treaty, 44 Op. O.L.C. ___, slip op. at 14–15 (Sept. 22, 2020), https://www.justice.gov/olc/file/1348136/download [hereinafter OLC Open Skies Opinion]. For more background on OLC's Open Skies Treaty memorandum and its implications for Congress, see CRS Legal Sidebar LSB10600, OLC: Congressional Notice Period Prior to Withdrawing from Treaty Unconstitutional, by Jennifer K. Elsea.

See National Defense Authorization Act for Fiscal Year 2020, Pub. L No. 116-92, § 1234, 133 Stat. 1198, 1648 (codified in 22 U.S.C. § 2593a note).

OLC Open Skies Opinion, slip op. at 31.

See Memorandum from David J. Barron, Acting Assistant Att'y Gen., Office of Legal Counsel, to Att'ys of the Office, Re: Best Practices for OLC Legal Advice and Written Opinions 1 (July 16, 2010), https://www.justice.gov/olc/pdf/olc-legal-advice-opinions.pdf ("OLC's core function ... is to provide controlling advice to Executive Branch officials on questions of law.")

See, e.g., McElroy v. United States ex rel. Guagliardo, 361 U.S. 281, 285–86 (1960) (declining to follow an Attorney General opinion and noting that such opinions are entitled to some weight but do not have the force of judicial decisions).

See, e.g., Jean Galbraith, The Runaway Presidential Power Over Diplomacy, 108 Va. L. Rev. 81 (2022).

Act of July 7, 1798, ch. 68, 1 Stat. 578.

See supra notes 232–237.

See supra notes 238–240.

See supra notes 248–250.

Third Restatement, supra note 1, § 102(2).

Id. § 102 cmt. c.

Id.

Id. § 102, reporters' n.2. The philosophy underlying the consistent objector exemption is that countries are bound by customary international law because they have at least tacitly consented to it. Binding them to abide by customary practices despite their explicit rejection of these norms would violate their sovereign rights—though countries are likely still bound in the case of peremptory, jus cogens norms, which are thought to permit no derogation of customary international law, such as the international prohibition against genocide or slavery. See Colombia v. Peru, 1950 I.C.J. 266 (Nov. 20, 1950); United Kingdom v. Norway, 1951 I.C.J. 116 (Dec. 18, 1951).

See supra "Conflict with Existing Laws."

Third Restatement, supra note 1, §102 (2) cmt. c. For a discussion of potential difficulties in relying U.N. General Assembly Resolutions as evidence of customary international law, see Oscar Schachter, International Law in Theory and Practice: General Course in Public International Law, 178 Rec. Des Cours 111–121 (1982-V).

See Sosa v. Alvarez-Machain, 542 U.S. 692, 738 (2004) (declining to apply protections espoused by the Universal Declaration of Human Rights because it "does not of its own force impose obligations as a matter of international law").

See, e.g., Andrew T. Guzman, Saving Customary International Law, 27 Mich. J. Int'l L. 115, 124–28 (2005) (discussing uncertainties associated with customary international law). See also Hamdan v. United States, 696 F.3d 1238, 1250 (D.C. Cir. 2012) (Kavanaugh, J.) ("It is often difficult to determine what constitutes customary international law, who defines customary international law, and how firmly established a norm has to be to qualify as a customary international law norm."), overruled on unrelated grounds by Al Bahlul v. United States, 767 F.3d 1 (D.C. Cir. 2014) (en banc).

Third Restatement, supra note 1, § 702, cmt. n.

Buell v. Mitchell, 274 F.3d 337 (6th Cir. 2001) (citing Comm. of U.S. Citizens Living in Nicar. v. Reagan, 859 F.2d 929, 940 (D.C. Cir. 1988); Third Restatement, supra note 1, § 102 (2) cmt. k & reporters' n.6).

See id. § 102(2).

Bradley, supra note 92, at 138.

See, e.g., Third Restatement, supra note 1, § 102 cmt. b (discussing the practice of states necessary for a rule of customary international law to become binding).

See The Nereide, 13 U.S. (9 Cranch) 388, 423 (1815) (Marshall, C.J.) ("[T]he Court is bound by the law of nations which is a part of the law of the land.); Respublica v. De Longchamps, 1 U.S. 111, 116 (Pa. O. & T. 1784) (describing a "crime in the indictment is an infraction of the law of Nations. This law, in its full extent, is part of the law of this State."). See also William Blackstone, Commentaries on the Laws of England 67 (1769) ("[T]he law of nations . . . is here adopted in its full extent by the common law, and is held to be a part of the law of the land.").

See, e.g., 1 Op. Att'y Gen. 26, 27 (1792) ("The law of nations, although not specially adopted by the constitution or any municipal act, is essentially the law of the land."); 1 Op. Att'y Gen. 69, 69 (1797) ("[T]he common law has adopted the law of nations in its full extent, made it a part of the law of the land.); 5 Op. Att'y Gen. 691, 692 (1802) ("[T]he law of nations is considered as part of the municipal law of each State.").

175 U.S. 677, 700 (1900) ("International law is part of our law, and must be ascertained and administered by the courts of justice of appropriate jurisdiction as often as questions of right depending upon it are duly presented for their determination.").

304 U.S. 64, 79 (1938) (describing the "assumption that there is a transcendental body of law outside of any particular State but obligatory within it unless and until changed by statute" as a fallacy) (internal quotation marks omitted).

Id.

See, e.g., Sosa v. Alvarez-Machain, 542 U.S. 692, 745–46 (2004) (Scalia, J., concurring) (arguing that customary international law would have been considered part of the "general common law" abolished by Erie); Curtis A. Bradley & Jack L. Goldsmith, Customary International Law As Federal Common Law: A Critique of the Modern Position, 110 Harv. L. Rev. 815, 852–55 (1997) ("After Erie ... a federal court can no longer apply [customary international law] in the absence of some domestic authorization to do so, as it could under the regime of general common law.").

See, e.g., Third Restatement, supra note 1, § 111 reporters' n.3 ("[T]he modern view is that customary international law in the United States is federal law.... "); Harold Hongju Koh, Is International Law Really State Law?, 111 Harv. L. Rev. 1824, 1835 (1998) ("[F]ederal courts retain legitimate authority to incorporate bona fide rules of customary international law into federal common law."); Beth Stephens, The Law of Our Land: Customary International Law As Federal Law After Erie, 66 Fordham L. Rev. 393, 397 (1997) ("[T]he suggestion that Erie tossed the law of nations out of federal court along with the general common law rests on several misconceptions.").

Banco Nacional de Cuba v. Sabbatino, 376 U.S. 398, 425 (1964) (discussing Philip C. Jessup, The Doctrine of Erie Railroad v. Tompkins Applied to International Law, 33 Am. J. Int'l L. 740 (1939)).

See Sosa, 542 U.S. at 730 ("We think it would be unreasonable to assume that the First Congress would have expected federal courts to lose all capacity to recognize enforceable international norms simply because the common law might lose some metaphysical cachet on the road to modern realism.").

See, e.g., Turkiye Halk Bankasi A.S. v. United States, 598 U.S. __, slip. op. at 7, 143 S. Ct. 940, 955 (2023) (Gorsuch, J., concurring in part and dissenting in part) ("Perhaps Article III incorporated customary international law into federal common law. But since [Erie] federal courts have largely disclaimed the power to develop federal common law outside of a few reserved areas.... And whether customary international law survives as a form of federal common law after Erie is a matter of considerable debate among scholars.") (internal citations omitted); Bradley, supra note 92, at 140–58. (providing an overview of competing views on customary international law's post-Erie status).

The Paquete Habana, 175 U.S. 677, 700 (1900).

See, e.g., Guaylupo-Moya v. Gonzales, 423 F.3d 121, 136 (2d Cir. 2005) ("[C]lear congressional action trumps customary international law and previously enacted treaties.").

Murray v. Schooner Charming Betsy, 6 U.S. (2 Cranch) 64, 118 (1804) (Marshall, J.) ("[A]n act of Congress ought never to be construed to violate the law of nations if any other possible construction remains.... "). But see Sampson v. Fed. Republic of Ger. & Claims Conf., 250 F.3d 1145, 1151–54 (7th Cir. 2001) (suggesting that given the "present uncertainty about the precise domestic role of customary international law," application of this canon of construction to resolve differences between ambiguous congressional statutes and customary international law should be used sparingly); Al-Bihani v. Obama, 619 F.3d 1, 32–36, 42 (D.C. Cir. 2010) (Kavanaugh, J., concurring in denial of rehearing en banc) (arguing against the application of the Charming Betsy canon).

See infra notes 285–287.

18 U.S.C. § 1651 ("Whoever, on the high seas, commits the crime of piracy as defined by the law of nations, and is afterwards brought into or found in the United States, shall be imprisoned for life.").

28 U.S.C. § 1605(a)(3) (providing an exception to foreign sovereign immunity in any case "in which rights in property taken in violation of international law are in issue and that property or any property exchanged for such property is present in the United States in connection with a commercial activity carried on in the United States by the foreign state").

28 U.S.C. § 1350.

For more in-depth treatment of the ATS, see CRS Report R44947, The Alien Tort Statute: A Primer, by Stephen P. Mulligan.

630 F.2d 876, 887–88 (2d Cir. 1980).

Id. at 878.

See Anthony D'Amato, Preface in The Alien Tort Claims Act: An Analytical Anthology vii (1999). See also Kiobel v. Royal Dutch Petroleum Co., 621 F.3d 111, 116 (2d Cir. 2010), aff'd on other grounds, 569 U.S. 108 (2013) ("Since [Filártiga], the ATS has given rise to an abundance of litigation in U.S. district courts."); Balintulo v. Daimler AG, 727 F.3d 174, 179 (2d Cir. 2013) (describing the ATS as "a statute, passed in 1789, that was rediscovered and revitalized by the courts in recent decades to permit aliens to sue for alleged serious violations of human rights occurring abroad"); Ingrid Wuerth, Kiobel v. Royal Dutch Petroleum Co.: The Supreme Court and the Alien Tort Statute, 107 Am. J. Int'l L. 601, 601 (2013) ("Since the 1980 court of appeals decision in Filártiga v. Peña-Irala permitting a wide of range human rights cases to go forward under the statute's auspices, the ATS has garnered worldwide attention and has become the main engine for transnational human rights litigation in the United States.").

542 U.S. 692 (2004).

Id. at 725.

Id. at 728.

See Kiobel, 569 U.S. at 124 (holding that the ATS does not apply extraterritorially in cases involving foreign plaintiffs against foreign defendants for conduct that occurred overseas); Jesner v. Arab Bank, PLC, 138 S. Ct. 1386, 1407 (2018) (holding that foreign corporations are not subject to the ATS claims); Nestlé USA, Inc. v. Doe, 141 S. Ct. 1931, 1937 (2021) (concluding that allegations of "general corporate activity" and corporate decision-making from within the United States were not sufficient to plead the domestic conduct necessary for an ATS claim).

See, e.g., Christopher Ewell et al., Has the Alien Tort Statute Made a Difference? A Historical, Empirical, and Normative Assessment, 107 Cornell L. Rev. 1206, 1209–10 (2022); Chimène Keitner, ATS, RIP?, Lawfare (Apr. 25, 2018), https://lawfareblog.com/ats-rip.

See supra "Executive Agreements."

See infra "Self-Executing vs. Non-Self-Executing Agreements."

See Bradley, supra note 92, at 335.

See supra "Choosing Between a Treaty and an Executive Agreement;" "Self-Executing vs. Non-Self-Executing Agreements;" "Relationship Between Customary International Law and Domestic Law."

See supra "Choosing Between a Treaty and an Executive Agreement."

See supra "Withdrawal from International Agreements."

For background on Congress's oversight and investigation powers, see CRS In Focus IF10015, Congressional Oversight and Investigations, by Todd Garvey, Mark J. Oleszek, and Ben Wilhelm.

See supra "Executive Agreements."

See supra "Transparency Requirements."

See supra "Congressional Implementation of International Agreements."

See supra "Conflict with Existing Laws."

See supra "Treaties."