The Shadow Cabinet is made up of frontbench MPs and Members of the Lords from the second largest party, or official Opposition party. The Opposition party appoints an MP to 'shadow' each of the members of the Cabinet. In this way the Opposition can make sure that it looks at every part of the Government and can question them thoroughly. It also means that the Opposition has MPs and Lords that are ready to take specific jobs in the Cabinet if they win at the next General Election. In the House of Lords the term "spokesperson" is used instead of "shadow".
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Her Majesty's Official Opposition
Related glossary term: Cabinet