In the House of Commons the Test Roll is the book that new MPs sign when they are sworn in after a General Election or a by-election. The MPs sign their name and their constituency. The term Test Roll comes from the fact that at one time MPs had to sign a roll of parchment to test that they accepted the Monarch as the head of the Church of England.
In the House of Lords, Life Peers sign the Test Roll during their introduction ceremony after taking the oath.
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Related glossary term: Oath of Allegiance