Introduction

Border security policy debates in the 21^st century often focused on enhancing and expanding barriers on the southwest border. These debates have become central to the interactions between Congress and the Administrations of both parties.

This report briefly contextualizes the history of U.S. enforcement of the U.S.-Mexico border, before outlining the available information on the Department of Homeland Security (DHS) border barrier funding and construction from 2005 through January 20, 2021.

Information on developments after January 2021 can be found in CRS Report R47979, DHS Border Barrier Funding Developments: FY2021-FY2024, by William L. Painter. This report will not be updated.

Historical Context

Establishment and Policing of the U.S.-Mexico Border

The Treaty of Guadalupe Hidalgo in 1848, with the cession of land to the United States, ended the Mexican-American War and set forth an agreed-upon boundary line between the United States and Mexico. The physical demarcation of the boundary was essentially set by the Gadsden Purchase, finalized in 1854, with some minor adjustments since then.¹

Securing U.S. borders has primarily been the mission of the U.S. Border Patrol, which was established by Congress by an appropriations act in 1924.² Initially, a relatively small force of 450 officers patrolled both the northern and southern borders between inspection stations, guarding against the smuggling of contraband and unauthorized migrants.³

The Immigration Act of 1924⁴ established immigration quotas for most countries, with the exception of those in the Western Hemisphere, including Mexico. (While some specific limitations existed, per-country quotas for Western Hemisphere countries did not exist until 1976.⁵) Earlier policies had set categorical exclusions to entry (e.g., for Chinese and other Asian immigrants) that were exceptions to an otherwise open immigration policy. Between 1942 and 1964, the Bracero Program brought in nearly 5 million Mexican agricultural workers to fill the labor gap caused by World War II. Both employers and employees became used to the seasonal work, and when the program ended, many continued this employment arrangement without legal authorization.⁶ Debates about enhancing enforcement of immigration laws ensued in the late 1970s and 1980s, largely in concert with counter-drug smuggling efforts⁷ and interest in curbing the rise in unauthorized flows of migrant workers.

Today, the United States' southern border with Mexico runs for nearly 2,000 miles over diverse terrain, through varied population densities, and across discontinuous sections of public, private, and tribal land ownership.⁸

Emergence of Barriers as Deterrence

A significant effort to construct barriers on the southern border as a deterrent to illegal entry by migrants or smugglers into the United States began in the early 1990s. In 1991, U.S. Navy engineers built a ten-foot-high corrugated steel barrier between San Diego and Tijuana made of surplus aircraft landing mats, to upgrade the previous chain-link fencing.⁹

In 1994, the Border Patrol (then part of the Department of Justice under the Immigration and Naturalization Service, INS) released a strategic plan for enforcing immigration laws along the U.S. border, as a part of a series of immigration reform initiatives.¹⁰ The plan, developed by Chief Patrol Agents, Border Patrol headquarters staff, and planning experts from the Department of Defense Center for Low Intensity Conflict, described their approach to improving control of the border through a strategy of "prevention through deterrence," under which resources were concentrated in major entry corridors to establish control of those areas and force traffic to more difficult crossing areas.

The Border Patrol will increase the number of agents on the line and make effective use of technology, raising the risk of apprehension high enough to be an effective deterrent. Because the deterrent effect of apprehensions does not become effective in stopping the flow until apprehensions approach 100 percent of those attempting entry, the strategic objective is to maximize the apprehension rate. Although a 100 percent apprehension rate is an unrealistic goal, we believe we can achieve a rate of apprehensions sufficiently high to raise the risk of apprehension to the point that many will consider it futile to continue to attempt illegal entry.¹¹

Prior to 1996, federal statute neither explicitly authorized nor required barrier construction along international borders.¹² In 1996, the Illegal Immigration Reform and Immigrant Responsibility Act of 1996 (IIRIRA) was enacted, and Section 102(a) specifically directed the Attorney General¹³ to "install additional physical barriers and roads ... in the vicinity of the United States border to deter illegal crossings in areas of high illegal entry into the United States."¹⁴

From INS (in Department of Justice) to CBP (in Homeland Security)

Following the terrorist attacks of September 11, 2001, the U.S. government changed its approach to homeland security issues, including control of the border. As a part of the establishment of DHS in 2003, INS was dismantled, and the Border Patrol and its responsibility for border security were moved from the Department of Justice to DHS as a part of U.S. Customs and Border Protection (CBP).¹⁵ CBP's border security responsibilities include the construction and maintenance of tactical infrastructure such as border barriers, but also the installation and monitoring of surveillance technology, and the deployment of border patrol agents to impede unlawful entries of people and contraband into the United States (e.g., unauthorized migrants, terrorists, firearms, and narcotics). CBP also maintains operations and staffing at official ports of entry through their Office of Field Operations (OFO).

The newly constituted DHS and CBP began operations in 2003 with transferred resources, and received their first annual appropriations for FY2004.

DHS Border Barriers: Legislative Era (2005-2016)

Built barriers, such as fencing, are a relatively new feature on most of the southern border.

During the 109^th and the first session of the 110^th Congresses (2005-2007), comprehensive immigration reform legislation and narrower border security measures were debated. One result was that Congress explicitly authorized and funded new construction of additional border barriers, significantly increasing their presence.

Enacted Authorizations and Appropriations

In the 109^th Congress, two bills were enacted that amended Section 102 of IIRIRA, easing the construction of additional border barriers. Section 102 of the REAL ID Act of 2005 (P.L. 109-13, Div. B) included broad waiver authority that allowed for expedited construction of border barriers.¹⁶ The Secure Fence Act of 2006 (P.L. 109-367) directed the Secretary of Homeland Security to "achieve and maintain operational control over the entire international land and maritime borders of the United States," mandated the construction of certain border barriers and technology on the border with Mexico by the end of 2008, and required annual reports on progress on border control.

This was a different approach in border barrier legislation. Past immigration policy bills had included border barriers as a part of a suite of remedies across government to the border security problem in the context of immigration policy. The Secure Fence Act of 2006 instead provided authorization for DHS alone to achieve "operational control" of the border through barriers, tactical infrastructure, and surveillance while largely not addressing the broader set of immigration policies that could contribute to improved border security.¹⁷ In addition, the Secure Fence Act of 2006 substantially revised IIRIRA Section 102(b) to include five specific border areas to be covered by the installation of fencing, additional barriers, and technology.

The FY2006 DHS Appropriations Act (P.L. 109-90) provided the first appropriations specifically designated for the Border Patrol (now under CBP and a part of DHS) to construct border barriers.¹⁸ The act specified $35 million for CBP's San Diego sector fencing.¹⁹ This funding was part of a surge in CBP construction spending from $91.7 million in FY2005—and $93.4 million in the FY2006 request—to $270.0 million for FY2006 enacted appropriations. This direction also represented the first specific statutory direction provided to CBP on the use of its construction funds.

Toward the end of 2007, Congress amended Section 102 of IIRIRA through Section 564 of the Consolidated Appropriations Act, 2008. Congress again required the construction of reinforced fencing along at least 700 miles of the U.S.-Mexico border, where it would be "most practical and effective,"²⁰ but also included flexibility in implementing this requirement, stating that

nothing in this paragraph shall require the Secretary of Homeland Security to install fencing, physical barriers, roads, lighting, cameras, and sensors in a particular location along an international border of the United States, if the Secretary determines that the use or placement of such resources is not the most appropriate means to achieve and maintain operational control over the international border at such location.²¹

The "BSFIT" Appropriation

Starting in FY2007 and continuing through FY2016, border barrier funding in CBP's budget was included in the "Border Security Fencing, Infrastructure, and Technology" (BSFIT) appropriation. When BSFIT was established in the Department of Homeland Security Appropriations Act, 2007 (P.L. 109-295), it consolidated border technology and tactical infrastructure funding from other accounts, including CBP's Construction appropriation and Salaries and Expenses appropriation.²²

According to the FY2007 DHS appropriations conference report, Congress provided $1,512,565,000 for BSFIT activities for FY2007: $1,187,565,000 from annual appropriations in P.L. 109-295, and $325,000,000 in prior enacted supplemental appropriations from P.L. 109-234 and other legislation. Congress directed portions of that initial appropriation to two specific border security projects, and withheld $950 million until a spending plan for a border barrier was provided. Starting in FY2008, a PPA²³ for "Development and Deployment" of technology and tactical infrastructure was included at congressional direction under the BSFIT appropriation.²⁴

The BSFIT Development and Deployment PPA was the first consistently structured year-to-year direction from Congress to CBP regarding putting border security technology and infrastructure in the field, covering FY2008-FY2016.

Figure 1 shows the requested and enacted levels for the Development and Deployment PPA from FY2008 through FY2016. Although it does not show an almost $1.2 billion FY2007 appropriation for border infrastructure before the Development and Deployment PPA was implemented, it does indicate the early high levels of investment in border infrastructure, which then tapered off. The dashed line shows the size of the budget request for these elements.

Figure 1. Development and Deployment PPA Request and Enacted Level, FY2008-FY2016 Millions of Nominal Dollars of Budget Authority

Source: CRS analysis of DHS Appropriations conference reports. Notes: "Development and Deployment" is a PPA (division) of the Border Security Fencing, Infrastructure, and Technology (BSFIT) appropriation for putting technology and tactical infrastructure in the field. In FY2007 $1,187,565,000 was appropriated for BSFIT without a formal request or appropriation reflecting the Development and Deployment structure.

The BSFIT Development and Deployment structure remained unchanged from its establishment until the implementation of the Common Appropriations Structure (CAS) for DHS in the FY2017 appropriations cycle, which redistributed BSFIT funding into two separate and broader appropriations. This implementation has complicated efforts to make detailed comparisons in funding levels across the time periods before and after FY2016.²⁵

Identifying Border Barrier Funding within BSFIT

The level of detail in DHS budget requests or appropriations bills and reports was not always sufficient to identify the specific funding levels for barrier construction. CRS was able to obtain more granular information directly from CBP, which provided a breakdown to CRS of its spending on border barriers beginning with FY2007.²⁶ The primary program that funded barrier construction in this period was the Tactical Infrastructure (TI) Program.²⁷

Figure 2 and Table 1 present funding data provided by CBP for border barriers under the TI program.²⁸ The funding provided in FY2007 to FY2009 resulted in increased border barrier construction (which extended for a few years into the early 2010s). As the funds for construction were expended, CBP transitioned its border barrier activities to primarily maintenance and minor repairs.

At the end of FY2016, approximately 654 miles—roughly one-third of the international boundary—had a primary layer of barriers.²⁹ Approximately 300 miles of the primary barrier was designed to prevent vehicles from entering, and approximately 350 additional miles was designed to block people on foot (i.e., pedestrian fencing). CBP has used various materials for pedestrian fencing, including bollard, steel mesh, and chain link, and employed bollard and Normandy-style fencing for vehicle barriers.³⁰ In certain areas, the primary layer was backed by a secondary layer of pedestrian fencing as well as, in rare cases, tertiary fencing (typically to delineate property lines).

Figure 2. CBP-Reported Data on Border Barrier Funding, FY2007-FY2016 Millions of Nominal Dollars

Source: U.S. Customs and Border Protection, "Summary of Historical Spending for TI and Wall Programs," email attachment sent to CRS November 26, 2018. Note: Data provided in Table 1.

DHS Border Barriers: Executive Era (2017- 2021)

On January 25, 2017, the Trump Administration issued Executive Order 13767, "Border Security and Immigration Enforcement Improvements." Section 2(a) of the EO indicated that it was the policy of the executive branch to "secure the southern border of the United States through the immediate construction of a physical wall on the southern border, monitored and supported by adequate personnel so as to prevent illegal immigration, drug and human trafficking, and acts of terrorism." The EO went on to define "wall" as "a contiguous, physical wall or other similarly secure, contiguous, and impassable physical barrier."³¹

Enacted Appropriations

Changes in Structure

For FY2017, changes were made both in the structure of how funds were appropriated, and how CBP organized those funds among its authorized activities.

The redistribution of appropriations into consistent functions across DHS components under the Common Appropriations Structure redistributed BSFIT funding into CBP's Operations and Support (OS) appropriation and the Procurement, Construction, and Improvements (PC&I) appropriation.³²

Border barrier design and construction funding, other than ports of entry, was included in the Border Security Assets and Infrastructure PPA under PC&I along with several other activities. It was initially identified as the "Wall Program." According to CBP, the program oversaw the execution of the FY2017 TI program funding and would be "responsible for all future wall construction."³³ In the FY2021 request, the Administration changed the name of the activity to the "Southwest Border Wall System."

A relatively small amount for operation and maintenance of CBP's border barriers was included under the Assets and Support PPA as part of the Border Patrol portion of CBP's OS appropriation. However, the debate focused primarily on the PC&I appropriation.

DHS Construction Funding for Border Barriers FY2017-2021

Table 2 shows appropriations for construction of border barriers requested by the Administration and provided by Congress in the DHS appropriations acts. Each fiscal year is discussed in detail after Table 2.

Legislative History of DHS Border Barrier Funding, FY2017-FY2021

FY2017

The Trump Administration submitted a supplemental appropriations request in March 2017 for a variety of priorities, including CBP staffing and border wall construction. The request for additional CBP PC&I funding included $1.38 billion, of which $999 million was for "planning, design, and construction of the first installment of the border wall."³⁴

The FY2017 DHS Appropriations bill included a sixth title with the congressional response to the supplemental appropriations request. It included $341.2 million to replace approximately 40 miles of existing primary pedestrian and vehicle barriers along the southwest border "using previously deployed and operationally effective designs, such as currently deployed steel bollard designs, that prioritize agent safety" and to add gates to existing barriers.³⁵

FY2018

The Administration requested $1.72 billion for the Border Security Assets and Infrastructure PPA, including $1.57 million for construction of border barriers. In the FY2018 appropriations measure, Congress provided $1.74 billion, which, according to a House Appropriations Committee summary, included funding for "over 90 miles of physical barrier construction along the southern border—including replacement, bollards, and levee improvements."³⁶ Section 230 of the bill specified the following $1.375 billion for the following activities under the CBP PC&I appropriation:

• $445 million for 25 miles of primary pedestrian levee fencing in Rio Grande Valley (RGV) sector;
• $196 million for primary pedestrian fencing in RGV sector;
• $251 million for secondary replacement fencing in San Diego sector;
• $445 million for replacement of existing primary pedestrian fencing; and
• $38 million for border barrier planning and design.³⁷

The section went on to note that the funding for primary fencing "shall only be available for operationally effective designs deployed as of [May 5, 2017], such as currently deployed steel bollard designs that prioritize agent safety."³⁸

FY2019

The Administration initially requested $1.647 billion for the Border Security Assets and Infrastructure PPA. Budget justification documents noted that $1.6 billion was requested for the border wall.³⁹ The Administration reportedly requested $5.0 billion for the wall from Republican congressional leadership.⁴⁰ However, no publicly available modification of its request was presented to Congress until January 6, 2019. At that time, in the midst of a lapse in annual appropriations due in part to conflict over border barrier funding, the acting head of the Office of Management and Budget (OMB) submitted a letter seeking $7 billion in additional border related funding.⁴¹ The $7 billion included $4.1 billion more for "the wall" than the Administration originally requested. The letter indicated that the total request of $5.7 billion would pay for "approximately 234 miles of new physical barrier and fully fund the top 10 priorities in CBP's Border Security Improvement Plan."

P.L. 116-6, the Consolidated Appropriations Act, 2019, included $1.375 billion for CBP "for the construction of primary pedestrian fencing, including levee pedestrian fencing, in the Rio Grande Valley Sector." Funding could only be used for "operationally effective designs deployed as of [May 5, 2017], such as currently deployed steel bollard designs that prioritize agent safety."⁴²

The same day President Trump signed the FY2019 consolidated appropriations act into law, he announced his intention to apply additional assets to border barrier construction. See "Border Barrier Funding Outside the Appropriations Process," below.

FY2020

In February 2019, the Administration requested $5.402 billion for the Border Security Assets and Infrastructure PPA. This included $5 billion in border barrier funding for FY2020, to support the construction of approximately 206 miles of border wall system.⁴³

The House Appropriations Committee included no funding for border barriers when it reported its FY2020 DHS appropriations bill.⁴⁴ In addition, the bill would have restricted the ability to transfer or reprogram funds for border barrier construction and proposed rescinding $601 million from funding appropriated for border barriers in FY2019.⁴⁵ The Senate Appropriations Committee took the opposite approach when it reported S. 2582 (116^th Congress), recommending $5 billion for border barrier construction. It also did not include any of the House bill's proposed restrictions or the rescission. Neither the House nor the Senate considered these appropriations bills on the floor.

The FY2020 DHS Appropriations Act (P.L. 116-93, Div. D)—which was passed as part of the Consolidated Appropriations Act, 2020—included $1.375 billion for "construction of barrier system along the southwest border."⁴⁶ The barrier system design restrictions were similar to prior years, with a new exception for designs that help "mitigate community or environmental impacts."⁴⁷ There was an additional requirement that the barriers are to be built in the highest priority locations identified in CBP's Border Security Improvement Plan.⁴⁸

FY2021

In February 2020, the Administration requested $2.060 billion for the Border Security Assets and Infrastructure PPA. This included $1.965 billion in border barrier funding for FY2021, to support the construction of 82 miles of border wall system.⁴⁹

Funding was not included in the House committee-reported bill, but $1.964 billion was included in the Senate majority draft legislation. The consolidated appropriations act for FY2021 ultimately included $1.375 billion for border barrier construction.⁵⁰

Comparing DHS Border Barrier Funding Levels Across Eras

Figure 3 presents a comparison of the total funding made available in the first and second eras of DHS efforts to support planning and construction of barriers on the U.S.-Mexico border.

This comparison is made with two important caveats: the data sources and funding structures were different in the two eras. In the legislative era (FY2007-FY2016), detailed information was provided directly to CRS in a communication from CBP. It was tracked for "tactical infrastructure," which included funding for border roads and other TI. In the executive era identified in this report (FY2017 into FY2021), data from CBP and appropriations measures (which has been more detailed with respect to barrier planning and construction) were generally consistent, but the Trump Administration also used the specifically defined "border wall" program to track most of the funding.

Figure 3. DHS Funding Available for Border Barrier Construction,* FY2007-FY2021 Millions of Nominal Dollars of Budget Authority

Sources: CRS analysis of U.S. Customs and Border Protection, "Summary of Historical Spending for TI and Wall Programs," email attachment sent to CRS November 26, 2018; CBP Budget Justifications and appropriations committee reports and conference reports for FY2019-FY2021. Notes: TI = Tactical Infrastructure. "Transferred from Treasury" indicates $601 million transferred to DHS from the Treasury Asset Forfeiture Fund to support border barrier funding. *This does not include $2.5 billion in FY2019 DOD counterdrug funding and $3.6 billion in FY2019 military construction funding, as those funds were not under DHS control.

Border Barrier Funding Execution: January 2017 to January 2021

Over the course of the Trump Administration's push for border barrier construction, the Government Accountability Office wrote a number of reports examining the process and results of this activity. GAO has access to extensive information beyond the public record regarding the execution of border barrier funding—information beyond what is available to CRS. GAO's nonpartisan oversight mission and expertise provides a useful perspective on how border barriers have been developed in recent years. References from GAO's summaries follow:

Southwest Border Security: Additional Actions Needed to Better Assess Fencing's Contributions to Operations and Provide Guidance for Identifying Capability Gaps (GAO-17-331), February, 2017:

Border fencing is intended to benefit border security operations in various ways, according to officials from the U.S. Border Patrol…. For example, according to officials, border fencing supports Border Patrol agents' ability to execute essential tasks, such as identifying illicit-cross border activities. CBP collects data that could help provide insight into how border fencing contributes to border security operations, including the location of illegal entries. However, CBP has not developed metrics that systematically use these, among other data it collects, to assess the contributions of border fencing to its mission. For example, CBP could potentially use these data to determine the extent to which border fencing diverts illegal entrants into more rural and remote environments, and border fencing's impact, if any, on apprehension rates over time. Developing metrics to assess the contributions of fencing to border security operations could better position CBP to make resource allocation decisions with the best information available to inform competing mission priorities and investments.⁶⁰

Southwest Border Security: CBP Is Evaluating Designs and Locations for Border Barriers but Is Proceeding Without Key Information (GAO-18-614), July, 2018:

CBP and U.S. Border Patrol developed a methodology for prioritizing future barrier deployments along the entire southwest border, which included input from Border Patrol officials, data on illegal entry traffic, and analysis of operational and engineering feasibility for each potential location. However, the strategy did not include analysis of the costs associated with deploying barriers in each location or segment, which can vary depending on topography, land ownership, and other factors. Without assessing costs, consistent with leading practices for capital decision making, CBP does not have complete information for prioritizing locations to use its resources in the most cost-effective manner.⁶¹

DHS Annual Assessment: Most Acquisition Programs Are Meeting Goals but Data Provided to Congress Lacks Context Needed For Effective Oversight (GAO-21-175), January, 2021:

CBP officials stated that land access and acquisition issues are significant challenges and could affect the Border Wall System Program's ability to meet its schedule goals.

The program develops acquisition program baselines (APB) for new segments as funding becomes available. As of September 2020, DHS leadership had approved two APBs for the program—for funding received in fiscal years 2018 and 2019—and CBP's Component Acquisition Executive had approved the program's preliminary APB associated with fiscal year 2020 funding.

The Border Wall System Program APBs do not account for related construction efforts that may limit oversight of the entire border wall system. For example, DOD has also provided support and funding for the construction of barriers and infrastructure along the southern border.… CBP officials told GAO that, although they provided a prioritized list of segments and construction standards to DOD, they have limited insight into DOD's planned efforts.⁶²

GAO noted in analyses of the FY2018 APB that the program was behind schedule by 15 months in the Rio Grande Valley and three months behind in San Diego due to delays in land acquisition.⁶³ They also noted CBP anticipated a funding shortfall in operation and support costs for FY2019 and FY2020 projects, which would require additional appropriations to cover.⁶⁴

Southwest Border: Schedule Considerations Drove Army Corps of Engineers' Approaches to Awarding Construction Contracts through 2020 (GAO-21-372), June 2021:

Some Department of Defense funding was only available for a short time before expiring, giving the Corps a tight schedule for awarding contracts. This—and the emergency declaration—led the Corps to depart from its planned acquisition approach.

The Corps focused on starting construction quickly and maximizing the miles of border barrier panels it could build. To do so, it:

* Awarded $4.3 billion in noncompetitive contracts. Competition helps ensure the government gets a good price.

* Started work before agreeing to terms. The Corps awarded several contracts before terms, such as barrier specifications and cost, were finalized.

By focusing on expediency in contracting, the government risks paying higher costs.

Contractors completed most DOD-funded border barrier panels by the end of December 2020 as scheduled.⁶⁵

In this report, GAO also noted a distinction between the construction of border barriers and the completion of a border wall system. The former is simply the placement of barrier panels, while the latter includes the sensors, lighting, and roads to deliver the operational capabilities DHS requires. GAO reported 345 miles of border barriers were built using counterdrug and military construction funding, and 112 miles were built using DHS funding. Sixty-nine6miles of contracted border wall system was completed – all on contracts awarded with DHS funding. Table 3 provides GAO's breakdown of mileage and funding by budget source.

GAO went on to note this about the status of construction activity as of January 2021:

All 13 DOD-funded contracts were expected to complete at least some wall panels by the end of 2020. Prior to the direction to pause work, 12 of these contracts were expected to be finished by the end of fiscal year 2021—i.e., the wall system was expected to be completed for most of the 391 miles awarded. While seven of the 18 contracts for border wall construction that were funded by DHS appropriations were completed, the completion timelines and construction status for the remaining DHS-funded contracts varied. Several were pushed back until fiscal year 2022 or suspended prior to the direction to pause work, and the completion status of the remaining miles is uncertain. According to CBP officials, these suspensions were related to difficulties they experienced in certifying real estate availability, which led USACE to pause construction activities, although design activities continued until the work stoppage.⁶⁶

Change in Administration, Change in Policy

On January 20, 2021, President Joe Biden terminated the Trump Administration's national emergency with respect to the southern border, stating: "It shall be the policy of my Administration that no more American taxpayer dollars be diverted to construct a border wall."⁶⁹ The proclamation went on to direct a pause in construction and obligation of funds related to the construction of barriers, to the extent permitted by law, and directed agencies to collect a range of data with consideration to repurposing barrier-related contracts. The Secretary of Defense and the Secretary of Homeland Security, in consultation with a range of executive departments and agencies were to

develop a plan for redirection of funds concerning the southern border wall, as appropriate and consistent with applicable law. The process of developing the plan shall include consideration of terminating or repurposing contracts with private contractors engaged in wall construction, while providing for the expenditure of any funds that the Congress expressly appropriated for wall construction, consistent with their appropriated purpose.⁷⁰

Questions Raised by Recent Border Barrier Funding

The Role of Congress v. the Administration in Funding

Section 4 of E.O. 13767, "Physical Security of the Southern Border of the United States," focused almost entirely on the construction of "a physical wall" on the U.S.-Mexico border as a means of obtaining operational control of the nearly 2,000-mile border.⁷¹ To briefly recap the funding that was provided by Congress in response to the Trump Administration's initiative, the $5.84 billion in appropriations provided by Congress to CBP for border barrier planning and construction for FY2017-FY2021 more than doubled the amount provided for those purposes in the BSFIT account for FY2007 to FY2016. Of the $5.84 billion

• $1.04 billion was specifically directed to barrier replacement projects;
• $2.02 billion was specifically directed to construction needs in the Rio Grande Valley Sector; and
• $2.78 billion was provided for planning and construction of border barriers without specific direction in regards to location or whether the funding was for barrier replacement or construction of additional miles of barriers.

Despite the historically high volume of resources provided, the Trump Administration took unprecedented steps—noted in "Border Barrier Funding Outside the Appropriations Process" above—to redirect additional federal funds to this purpose, making almost $10 billion available to the Department of Defense to undertake a task for which the primary authority lay with CBP.

• In a situation where Congress has assessed the Administration's case for funding a given initiative, and chosen to only provide limited funding, how can Congress best maintain its Constitutional "power of the purse" when an Administration chooses to disregard appropriations law precedents and practices?
• Conversely, when Congress has appropriated funds for a given purpose, and an Administration—new or incumbent—chooses to change the policy that Congress has specifically funded, what avenues should be available for Congress to either provide flexibility on the use of those funds, or insist on its position and ensure the funding is used as directed?

The Role of Congress v. the Administration in Execution and Oversight

Congress has at times been challenged in obtaining information on border barrier construction for use in public debate. Generally, the Trump Administration (and the Biden Administration thereafter), in discussions about border barriers, relied on the U.S. Border Patrol Impedance and Denial Prioritization Strategy, which includes a list of projects for barrier construction. This is not a document available for use in public debate, as it is a report to a specific committee of Congress, and it contents, while not classified information, are restricted from public circulation.⁷²

There were no known authoritative cost estimates for the total construction or operation and maintenance costs of these projects if they were all completed, or publicly available assessments of how completion of various projects might affect CBP's operational costs. As noted above, the GAO reported in 2018 that CBP's methodology for prioritizing border barrier deployments did not use cost estimates that included analysis of the costs associated with deploying barriers in each location, such as those driven by topography, land ownership, and other factors.⁷³ Furthermore, GAO reported in 2016 that the border barriers' contributions to CBP goals were not being adequately measured.⁷⁴

As long as this issue is a matter of congressional debate, Congress may wish to obtain additional information and explore the following questions in assessing border barrier funding proposals:

• What are the projected operation and maintenance costs for the existing southwest border barriers? How will those change with the continuing maintenance needs for replacements and upgrades, or new construction of barriers?
• How is CBP prioritizing further border wall system work? What level of transparency is possible without compromising operational effectiveness and efficiency?
• What are the projected land acquisition and construction costs of CBP's remaining top priority border barrier projects, based on unique topography, land ownership, and strategic intent of the projects? What steps is CBP taking to control the growth of those costs? Who within the Administration is providing oversight of how these funds are used, and are they reporting their findings to Congress?
• Are existing barriers and completed improvements having measurable impacts on illegal entries into the U.S. and smuggling of contraband? How are CBP and other stakeholders making their assessments? Is CBP getting its desired tactical or strategic outcomes?
• Are the operational benefits worth the financial and operational costs, or are there more efficient ways to achieve the desired tactical or strategic outcomes?