United States congressional conference committee
A conference committee is a committee of the Congress appointed by the House of Representatives and Senate to resolve disagreements on a particular bill. The conference committee is usually composed of the senior Members of the standing committees of each House that originally considered the legislation.
Going to conference 
Conference committees operate after the House and the Senate have passed different versions of a bill. Conference committees exist to draft a compromise bill that both houses can accept. Both houses of Congress must eventually pass the identical legislation for the bill to become law. (See U.S. Const., art I, sec. 7.) The two houses can reach that identical product through the process of amendments between Houses, where the House passes the Senate bill with a House amendment, or vice versa, but this process can be cumbersome. Thus most major bills become law through using a conference committee. (See Sen. Procedure, 449.)
After one house passes a bill, the second house will often pass the same bill, with an amendment representing the second house’s work product. The second house will then send a message between houses to the first house, asking the first house to concur with the second house’s amendment. If the first house does not like the second house’s amendment, then the first house can disagree with the amendment of the second house, request a conference, appoint conferees, and send a message to that effect to the second house. The second house then insists on its amendment, agrees to a conference, and appoints conferees.
Each house determines the number of conferees from its house. The number of conferees need not be equal from the two houses of Congress. In order to conclude its business, a majority of both House and Senate delegations to the conference must indicate their approval by signing the conference report.
The authority to appoint conferees lies in the entire House, and the entire Senate can appoint conferees by adopting a debatable motion to do so. (See Cong. Rec., 18 June 1968, 17,618–24; Sen. Procedure, 455.) But leadership have increasingly exercised authority in the appointment of conferees.
The House and Senate may instruct conferees, but these instructions are not binding on conferees.
Conference committees can be extremely contentious, particularly if the houses are controlled by different parties. House rules require that one conference meeting be open to the public, unless the House, in open session, votes that a meeting will be closed to the public. But apart from this one open meeting, conference committees usually meet in private, and are dominated by the Chairs of the House and Senate Committees.
House and Senate rules forbid Conferees from inserting in their report matter not committed to them by either House. (See House Rule XXII, Senate Rule XXVIII.) But conference committees sometimes do introduce new matter. In such a case, the rules of each House provide that a Member may object through a point of order, although each House has procedures under which it can vote to waive the point of order. The House provides a procedure by which the offending provision may be stricken from the bill. Formerly, the Senate required a Senator to object to the whole bill as reported by the conference committee. If the objection was well founded, the Presiding Officer ruled, and a Senator could appeal the ruling of the Chair. If the appeal was sustained by a majority of the Senate, it had precedential effect, eroding the rule on the scope of conference committees. Thus from fall 1996 through 2000, the Senate had no limit on the scope of conference reports, and some argued that the majority abused the power of conference committees. (See, e.g., Dauster, “Five-Man Senate?”) In December 2000, the Senate reinstated the prohibition of inserting matters outside the scope of conference. (See Consolidated Appropriations for Fiscal Year 2001, Pub.L. 106–554, § 903 (2000), 114 Stat. 2763, 2763A-198.) The rule changed again with the Honest Leadership and Open Government Act (S. 1 of the 110th Congress), enacted in September 2007. Now any single Senator may raise a procedural objection — a point of order — against subject matter newly inserted by the conference committee without objecting to the rest of the bill. Proponents of the measure may move to waive the rule. The affirmative vote of 60 Senators is required to waive the rule. If the point of order is not waived and the Chair rules that the objection is well-founded, only the offending provision is stricken from the measure, and the Senate votes on sending the balance of the measure back to the House. (See Senate Rule XXVIII.)
The conference report 
Most times, the conference committee produces a conference report melding the work of the House and Senate into a final version of the bill. A conference report proposes legislative language as an amendment to the bill committed to conference. And the conference report also includes a joint explanatory statement of the conference committee. This explanatory statement provides one of the best sources of legislative history on the bill. J. William Rehnquist observed that the joint conference report of both Houses of Congress is considered highly reliable legislative history when interpreting a statute.
Once a bill has been passed by a conference committee, it goes directly to the floor of both houses for a vote, and is not open to further amendment. In the first house to consider the conference, a Member may move to recommit the bill to the conference committee. But once the first house has passed the conference report, the conference committee is dissolved, and the second house to act can no longer recommit the bill to conference.
Conference reports are privileged. And in the Senate, a motion to proceed to a conference report is not debatable, although Senators can generally filibuster the conference report itself. The Congressional Budget Act of 1974 limits debate on conference reports on budget resolutions and budget reconciliation bills to 10 hours in the Senate, so Senators cannot filibuster those conference reports. (2 U.S.C. § 636, 2 U.S.C. § 641e.)
References and further reading 
- Simpson v. United States, 435 U.S. 6, 17-18 (1978) (Rehnquist, dissenting)
- Dauster, Bill. “Five-Man Senate? Rewriting the Rules on Conferences,” Roll Call, 10 Oct. 1996, 5.
- Dove, Robert B. "Conference Committees and Reports" in Enactment of a Law.
- Riddick, Floyd M., and Alan S. Frumin. “Conferences and Conference Reports” in Riddick's Senate Procedure, 449–93. Washington, D.C.: Government Printing Office, 1992.
- Johnson, Charles W. “Final Action” in How Our Laws Are Made, United States House of Representatives, 108th Congress, 1st Session, 2003.
- McCown, Ada C. The Congressional Conference Committee. New York: Columbia University Press, 1927.
- United States House of Representatives, Rules of the House, Rule XXII.
- United States Senate, Standing Rules of the Senate, Rule XXVIII.