Congressional commissions are formal groups established by Congress to provide independent advice, make recommendations for changes in public policy, study or investigate a particular problem or event, or perform a specific duty. Usually composed of policy experts chosen by Members of Congress and/or officials in the executive branch, commissions may hold hearings, conduct research, analyze data, investigate policy areas, or make field visits as they perform their duties. Most commissions complete their work by delivering their findings, recommendations, or advice in the form of a written report to Congress. Occasionally, legislation submitted by commissions will be given "fast track" authority in Congress. Although no legal definition exists for what constitutes a "congressional commission," in this report, a congressional commission is defined as a multi-member independent entity that (1) is established by Congress, (2) exists temporarily, (3) serves in an advisory capacity, (4) is appointed in part or whole by Members of Congress, and (5) reports to Congress. These five characteristics effectively serve to differentiate a congressional commission from a presidential commission, an executive branch commission, or other bodies with "commission" in their names. Over 100 congressional commissions have been established since 1989. Throughout American history, Congress has found commissions to be useful tools in the legislative process, and legislators continue to use them today. By establishing a commission, Congress can potentially provide a highly visible forum for important issues and assemble greater expertise than may be readily available within the legislature. Complex policy issues can be examined over a longer time period and in greater depth than may be practical for legislators. Finally, the non-partisan or bipartisan character of most congressional commissions may make their findings and recommendations more politically acceptable, both in Congress and among the public. Critics argue that many congressional commissions are established by legislators seeking "blame avoidance," and take difficult decisions out of the hands of Congress. Other observers have suggested that commissions are undemocratic, with their members neither electorally accountable to the public nor their meetings and decisionmaking processes public. Finally, some critics see commissions as financially inefficient, arguing that the costs of establishing a commission outweigh potential benefits, especially since their findings and recommendations may be ignored by Congress. Congressional commissions can be categorized as either policy commissions, investigatory commissions, or commemorative commissions. Most congressional commissions are policy commissions, such as the United States Commission on North American Energy Freedom, that study particular public policy problems and typically report their findings to Congress along with recommendations for legislative or executive action. Far fewer commissions are investigative commissions, such as the National Commission on Terrorist Attacks Upon the United States, that are established to examine past events. A small number of commissions are commemorative commissions, such as the Abraham Lincoln Bicentennial Commission, that plan, coordinate, and oversee celebrations of people or events, often in conjunction with milestone anniversaries. The temporary status of congressional commissions and short time period they are often given to complete their work product makes it important that legislators craft statutes creating congressional commissions with care. Statutes establishing congressional policy commissions generally include language that states the mandate of the commission, provides a membership structure and appointment scheme, defines member compensation and other benefits, outlines the commission's duties and powers, authorizes funding, and sets a termination date for the commission. A variety of options are available for each of these organizational choices. Legislators can tailor the composition, organization, and arrangements of a commission, based on particular goals. As a result, individual commissions often have organizational structures and powers quite different from one another. In the past, confusion has arisen over whether particular entities are "congressional commissions." There are several reasons for this confusion. First, the term "congressional commission" is not defined by law; observers might disagree as to whether an individual entity should be characterized as such. Second, many different entities within the federal government have the word "commission" in their name, such as regulatory commissions, presidential advisory commissions, and advisory commissions established in executive agencies. Conversely, many congressional commissions do not have the word commission in their name; instead, they are designated as boards, advisory panels, advisory committees, task forces, or by other terms. In this report, a congressional commission is defined as a multi-member independent entity that (1) is established by Congress, (2) exists temporarily, (3) serves in an advisory capacity, (4) is appointed in part or whole by Members of Congress, and (5) reports to Congress. This definition differentiates a congressional commission from a presidential commission, an executive branch commission, or other bodies with "commission" in their names, while including most entities that fulfill the role commonly perceived for commissions: studying policy problems and reporting findings to Congress. Each of these characteristics is discussed below. Congressional commissions are established by Congress, usually by statute. Not all advisory commissions established by statute, however, are congressional commissions. Congress routinely establishes advisory commissions in the executive branch by statute. Conversely, not all advisory commissions serving the federal government are established by Congress. Commissions may be established in the executive branch by the President, department heads, or individual agencies. Congressional commissions are also independent of Congress in function. This characteristic excludes commission-like entities established within Congress, such as congressional observer groups, working groups, and ad hoc commissions and advisory groups created by individual committees of Congress under their general authority to procure the "temporary services" of consultants to "make studies and advise the committee," pursuant to 2 U.S.C. 72a. Congressional commissions are established to perform specific tasks, with statutory termination dates linked to the completion of the tasks. This restriction excludes entities that typically serve an ongoing administrative purpose, do not have statutory termination dates, and do not produce reports, such as the House Office Building Commission or Senate Commission on Fine Art. Also excluded are entities that serve ongoing diplomatic or interparliamentary functions, such as the U.S. Group to the NATO Parliamentary Assembly, or the Canada-United States Interparliamentary Group. Finally, Congress has created a number of boards to oversee government entities, such as the United States Holocaust Memorial Council and the John F. Kennedy Center Board of Trustees. Although these entities could arguably be considered congressional commissions, their lifespan, purpose, and function differs from temporary congressional commissions. Unlike regulatory commissions, congressional commissions are not typically granted administrative authority, and they usually lack the power to implement their findings or recommendations. Instead, advisory commissions typically produce reports that present their findings and offer recommendations for either legislative or executive action. Congressional commissions provide that Members of Congress, particularly the leadership, be intimately involved in the appointment process, either through direct service on a commission, or by appointing or recommending candidates for membership. Congressional commissions are usually required to submit their reports to Congress, or to Congress and the President. Other advisory commissions, such as presidential or executive branch commissions, typically submit their reports only to the President or agency head. This report attempts to identify all congressional commissions established between the 101 st and 114 th Congress. A large number of bills creating congressional commissions are introduced in Congress each session. During the 114 th Congress, bills have been introduced that would have created more than 20 congressional commissions. Similar numbers of bills have been proposed in previous Congresses. Most of these bills proposing commissions are not enacted. A database search was conducted using the Legislative Information System (LIS) for the 101 st through 114 th Congresses (1989-2016). Each piece of legislation returned was examined to determine if (1) the legislation contained a commission; and (2) if the commission was an ad hoc congressional commission. If the commission was judged to be an ad hoc congressional commission, the name, public law number, Statutes-at-Large citation, and date of enactment were recorded. A total of 107 congressional commissions were identified through this search. Table 1 reports the number of commissions identified by the search in each Congress. Two caveats accompany these results. As stated above, identifying congressional commissions involves making judgment calls about particular characteristics. Second, tracking provisions of law that create congressional commissions is an inherently inexact exercise. Although many such bodies are created in easily identifiable freestanding statutes, others are contained within the statutory language of lengthy omnibus legislation. Consequently, individual commissions may have been missed by the search algorithm. Congressional commissions can be generally placed into one of three categories. Most congressional commissions are policy commissions , temporary bodies which study particular policy problems and report their findings to Congress. Less common are investigative commissions, which are similar in structure to policy commissions but tasked with reviewing specific events. C ommemorative commissions are entities established to commemorate a person or event, often to mark an anniversary. Table 2 reports the total number and percentage of each type of commission identified in the LIS database search of the 101 st through 114 th Congresses. The vast majority of congressional commissions, 79%, were established to study, examine, or review a particular policy problem. During the 110 th , 111 th , 113 th , and 114 th Congresses, policy commissions were established to study a range of issues, including the proliferation of weapons of mass destruction, motor fuel tax enforcement, surface transportation policy, defense policy, and the threat to the United States from Electromagnetic Pulse (EMP) attacks. Investigative commissions, established for the purpose of reviewing specific events, are much less common than policy commissions. Only seven such bodies have been established by Congress during the past 22 years. Investigative commissions, however, such as the National Commission on Terrorist Attacks Upon the United States (the 9/11 commission), often receive substantial public attention. Investigative commissions are often granted broad powers, including the power to subpoena witnesses. Most recently, the Commission on Wartime Contracting in Iraq and Afghanistan, the Congressional Oversight Panel for the Emergency Economic Stabilization Act, and the Financial Crisis Inquiry Commission were established during the 110 th and 111 th Congresses. Since 1989, Congress has created 15 commemorative congressional commissions.