The Committee of the Whole is a parliamentary device, derived from the practice of the English House of Commons, used to expedite the work of the House during the debate and amendment process. It involves several less formal arrangements to conduct business, including a lesser number of Members required for a quorum (100 as compared to 218 in the full House). It also has a different procedure required to obtain a recorded vote (25 Members standing in support as compared to the requirement of one-fifth of those present standing or a lack of a quorum in the full House). Certain motions allowed in the House are prohibited in the Committee of the Whole, such as motions for the previous question, to adjourn, to reconsider a vote, or to refer or recommit.

The Speaker does not preside in the Committee of the Whole, but appoints a Member of the majority party to preside with the full authority to keep order, rule on questions, recognize Members, and order votes. The Member designated to preside is addressed as “Mr. Chairman” or in the case of a female Member as “Madam Chairman.” On entering the House Chamber and facing the Chair, an easy way to determine whether the House is in the Committee of the Whole or in the full House is to note the position of the Mace to the left of the Chair. If it is in the lower position, the House is in the Committee of the Whole.

114th Congress Floor Procedures Manual