T he U.S. Constitution expressly grants each house of Congress the power to discipline its own Members for misconduct, including through expulsion, stating that: [e]ach House may determine the Rules of its Proceedings, punish its Members for disorderly Behaviour, and, with the Concurrence of two thirds, expel a Member. This report discusses the nature of the power of Congress to remove a Member, including the historical background of the Expulsion Clause, the implications of the limited judicial interpretations of the Clause's meaning, and other potential constitutional limitations in the exercise of the expulsion power. The report then explores a number of issues of debate as to Congress's power to expel, including whether past practice is legally binding on a given body; which acts may be sufficient to warrant expulsion; and whether acts that occurred prior to the Member's election or reelection to Congress are subject to the expulsion power. Expulsion is the process by which a house of Congress may remove one of its Members, after the Member has been duly elected and seated. Expulsion, which is expressly provided for in the Expulsion Clause, is often confused with exclusion, which is an implied power of Congress that stems from the Qualifications Clauses for the House and Senate. Exclusion occurs when a body of Congress refuses to seat a Member-elect. Unlike the two-thirds majority requirement of the expulsion power, a body of Congress may exclude a Member-elect with a simple majority. As the Supreme Court has explained, while exclusion and expulsion both bar an individual from holding a seat in Congress, the two actions exist for different purposes and occur at different times. Specifically, in Powell v. McCormack , the Court explored the constitutionality of Representative Adam Clayton Powell's exclusion from the House of Representatives. The impetus for the case was an investigation of expenditures authorized by Powell during the 89 th Congress, which concluded that, as chairman of a House committee, the Member had engaged in improper activities, including deceiving House authorities with regard to travel expenses and directing illegal payments to his wife. The House took no formal action with regard to those findings during that Congress, but refused to administer the oath of office to Powell at the start of the 90 th Congress the following year. Subsequently, a Select Committee, which was appointed at the outset of the 90 th Congress to determine Powell's eligibility to be seated as a Member, recommended that Powell be sworn into office as a Member and subsequently disciplined. However, the House rejected that recommendation and instead adopted a resolution that would exclude Powell, which it approved by a vote of 307 to 116. Powell sued to be reinstated and on appeal the Supreme Court held that Powell's exclusion was unconstitutional, explaining that "exclusion and expulsion are not fungible proceedings." While the Court recognized that the Constitution grants broad authority to each of the houses of Congress regarding expulsion and other discipline, it explained that Congress's authority regarding exclusion was limited to the enumerated qualifications requirements. Because of the distinct nature of each action, the Court emphasized that the vote to exclude Powell, despite exceeding a two-thirds majority, could not substitute for his expulsion. Discerning the constitutional meaning of the Expulsion Clause requires an examination of the text of the Clause, the historical background that undergirds the Clause, the limited judicial decisions that have sought to interpret its text, and a brief evaluation of how the Clause may be subject to limitation by other constitutional principles. In addition, and in light of the discretionary nature of the power, an assessment of House and Senate practice is necessary for a full understanding of the expulsion power. The Expulsion Clause states that "[e]ach House may [ ... ] punish its Members for disorderly Behaviour, and, with the Concurrence of two thirds, expel a Member." Thus, the sole textual standard expressly defined by the Constitution requires that expulsion of a Member of Congress may only be enforced "with the Concurrence of two-thirds." While the Expulsion Clause does not specify the measure of the two-thirds majority, the standard is generally understood to be assessed relative to the number of Members of that body who are present and voting. Similarly, the two-thirds majority requirement mirrors the standard by which Congress may likewise remove officials in the executive and judicial branches of government through the impeachment process. Like other constitutional provisions relating to the powers and privileges of the Congress, the origins of the Expulsion Clause lay with the practices of the English Parliament. The English House of Commons historically exercised an inherent authority to expel members by a simple majority vote. That power was viewed as one to be wielded at the body's "absolute discretion" with few recognized limitations, and as a result, it was historically utilized more liberally in England than it has been used in the United States. Moreover, the expulsion power was used in a relatively ad hoc manner with, for example, no established standards governing the type of conduct warranting expulsion. As a result, hundreds of members were expelled from Parliament prior to the turn of the 19 th century on grounds ranging from publishing slanderous writings to treason. Early parliamentary expulsions were motivated not only by a desire to preserve the integrity of the legislative process, but also to expel unpopular or dissenting legislators for political or religious reasons. One contemporary English expulsion case that influenced the members of the U.S. Constitutional Convention was that of John Wilkes. Wilkes was a Member of Parliament who in 1763 criticized the King's peace treaty with France. Wilkes was arrested, expelled from the House of Commons, and fled into exile. He later returned to England and was reelected to Parliament in 1768, only to be convicted of seditious libel and again expelled from the House. Wilkes was repeatedly reelected, but each time Parliament excluded him, prevented him from taking his seat, and ultimately declared him ineligible for reelection. Wilkes was finally permitted to serve following his election in 1774, after which the House of Commons expunged his expulsions and exclusions, acknowledging that it had acted in a manner "subversive of the rights of the whole body of electors of this kingdom." The English precedents and traditions concerning expulsion were incorporated into the proceedings of the colonial legislatures, where legislators were expelled for an equally wide array of reasons. But the Wilkes case had a "significant impact in the American colonies," and after the Revolution, "few expulsions occurred in the new state legislatures." Indeed, the abuse of the expulsion power by the House of Commons in the Wilkes case likely led to the two predominant constitutional restrictions on each house's authority to judge its membership and discipline its members: constitutionally fixed qualifications for service in the House and Senate and a two-thirds supermajority requirement to expel a Member. There was, however, seemingly no significant debate on the Expulsion Clause at the Constitutional Convention. Some insight, however, can be gleaned from the drafting history. Early draft versions of the Expulsion Clause, first arising from the Convention's Committee of Detail, distinguished between the power to expel and the power to punish members for "disorderly behavior." Based on earlier draft versions, it appears that the "disorderly behavior" language was entirely separate from, and therefore inapplicable to, the power to expel. It was not until late in the Convention's consideration of the provision that the body approved the two-thirds requirement for expulsion. James Madison recommended the addition, noting that "the right of expulsion was too important to be exercised by a bare majority.... " No mention was made at the Convention in regards to the type of misconduct that would warrant expulsion. Accordingly, it appears that the Founders viewed the chief barrier to the expulsion power's abuse as the procedural requirement of the approval of a supermajority of a house of Congress, as opposed to any substantive requirement that defines what sort of conduct warrants expulsion. The U.S. Supreme Court and lower federal courts have not decided a case directly bearing on the expulsion of a Member of Congress, although judicial discussions of the expulsion power have developed in dicta. The Supreme Court has stated, for example, that Congress's expulsion power "extends to all cases where the offence is such as in the judgment of the Senate is inconsistent with the trust and duty of a member." The Court highlighted that a Member's conduct could be subject to legislative discipline even if "[i]t was not a statutable offence nor was it committed in his official character, nor was it committed during the session of Congress, nor at the seat of government." The Court has also emphasized that the House and Senate may exercise the expulsion power exclusively, such that any prosecution by the executive of related offenses by the Member do not interfere with Congress's power to expel. These relatively few statements suggest a broad view of the expulsion power. A likely explanation for the lack of judicial precedent directly addressing questions arising under the Expulsion Clause may be found in the political question doctrine, a principle stemming from the Constitution's separation of powers. Courts have declined to decide cases involving "political questions," which are controversies where there is a "textually demonstrable constitutional commitment of the issue to a coordinate political department; or a lack of judicially discoverable and manageable standards for resolving it." In this vein, courts have been cognizant that the expulsion power, as a form of legislative discipline, exists separately from civil or criminal liability and empowers the respective houses of Congress to maintain the integrity and dignity of the legislature itself and its proceedings. The Supreme Court has reflected this reasoning in some of the cases that have touched on the Expulsion Clause. For example, in 1897, the Court discussed the Expulsion Power in a case of a petitioner convicted of criminal contempt for refusing to answer questions during a congressional investigation of potential misconduct of Members of Congress.