Committee of the Whole House

In the United Kingdom House of Commons, the Committee of the Whole House is used instead of a standing committee for the clause-by-clause debate of important or contentious bills. The sitting is presided over by the Chairman of Ways and Means, rather than the Speaker of the House.
In the United Kingdom House of Lords, the Committee of the Whole House examines the majority of bills.
References

BBC News: Politics: Committee of the Whole House
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