Call of the house

A quorum is the minimum number of members of a deliberative assembly (a body that uses parliamentary procedure, such as a legislature) necessary to conduct the business of that group. According to Robert's Rules of Order Newly Revised, the "requirement for a quorum is protection against totally unrepresentative action in the name of the body by an unduly small number of persons."

The term quorum is from a Middle English wording of the commission formerly issued to justices of the peace, derived from Latin quorum, "of whom", genitive plural of qui, "who". As a result, quora as plural of quorum is not a valid Latin formation.

Each assembly determines the number of members that constitutes a quorum in its governing documents (such as in its constitution, charter, bylaws or standing orders). The quorum may also be set by law. Robert's Rules of Order Newly Revised states that the quorum set in an organization's bylaws "should approximate the largest number that can be depended on to attend any meeting except in very bad weather or other extremely unfavorable conditions."

In the absence of such a provision, a quorum in an assembly whose membership can be determined is a majority of the entire membership. In the meetings of a convention, unless provided otherwise, a quorum is a majority of registered delegates, even if some have departed. In a mass meeting or in an organization in which the membership cannot be accurately determined, the quorum consists of those who attend the meeting.

In committees and boards, a quorum is a majority of the members of the board or committee unless provided otherwise. The board or committee cannot set its own quorum unless given such power. In a committee of the whole or its variants, a quorum is the same as the assembly unless otherwise provided.

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