The principle of majority rule dominates the work of the House of Representatives. This means that most questions are decided by vote of a simple majority, assuming the presence of a quorum. For instance, if all 435 lawmakers vote, the winning threshold is at least 218—one more than half the membership of the House. In cases of a tie vote, House Rule XX, clause 1(c), states that "a question shall be lost."

Some supermajority votes, however, are explicitly specified in the Constitution. Others are created by House rules. Under the constitutional power enabling each chamber to determine its own rules of proceedings (Article I, Section 5), the House may adopt a number of additional supermajority (sometimes called "extraordinary majority") requirements.

Constitutional Supermajority Requirements

The Framers of the Constitution generally favored decisionmaking by simple majority vote. On the other hand, they recognized the virtue of supermajority votes in certain circumstances. In Federalist No. 58, James Madison found that supermajority votes could serve as a "shield to some particular interests, and another obstacle generally to hasty and partial measures." Alexander Hamilton, too, in Federalist No. 73 highlighted the benefits of requiring an extraordinary majority of each chamber to overturn a President's veto. "It establishes a salutary check upon the legislative body," he said, "calculated to guard the community against the effects of faction, precipitancy, or of any impulse unfriendly to the public good, which may happen to influence a majority of that body."

The Constitution requires a two-thirds vote of the Members voting, a quorum being present, of either the House, the Senate, or both in five situations: (1) overriding presidential vetoes,¹ (2) voting to convict federal officers in impeachment trials (Senate),² (3) providing advice and consent to treaties (Senate),³ (4) expelling Members from the House or Senate,⁴ and (5) proposing constitutional amendments.⁵

In addition, Section 3 of the Fourteenth Amendment, ratified in 1868, disallows anyone who engaged in "insurrection or rebellion" from holding any civil or military office unless each house removed this disability by a two-thirds vote of each chamber. The Twenty-Fifth Amendment, ratified in 1967, addresses the issues of presidential succession and inability. The amendment provides that the House and Senate, by a two-thirds vote of each chamber, may determine that "the President is unable to discharge the powers and duties of his office."

Supermajority Requirements Under House Rules

The House has four rules that require a supermajority vote of the Members voting, a quorum being present, to pass legislation:

• 1. Rule XV, clause 1, requires a two-thirds vote to suspend the rules of the House.
• 2. Rule XV, clause 5, requires a two-thirds vote to dispense with the call of the Private Calendar on the first Tuesday of the month.
• 3. Rule XIII, clause 6(a), requires a two-thirds vote to consider a special rule on the same day that the Rules Committee reports it. This requirement does not apply during the last three days of a session.
• 4. Rule XXI, clause 5(b), requires a vote of not less than three-fifths of Members voting to approve legislation that increases federal income tax rates.⁶

The House may amend its rules by a simple majority, including House rules that mandate supermajority votes. In addition, the rules of the House may be waived through means such as adopting a special rule from the Rules Committee. By contrast, the supermajority votes established in the Constitution may not be waived by action of either chamber.