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Casting Vote

Casting Vote, the vote given by the president of an assembly when the votes upon the two sides of a question are equally balanced. Some derive the name from the fact that this vote casts the decisive weight into the one scale or the other. The Speaker of the House of Commons, and the chairmen of Select Committees, Ways and Means, and Committee of the whole House, vote only when the voting is equal. In some assemblies the chairman has a casting-vote besides his ordinary vote.