Parliamentary privilege

Parliamentary privilege is a legal immunity enjoyed by members of certain legislatures, in which legislators are granted protection against civil or criminal liability for actions done or statements made in the course of their legislative duties. It is common in countries whose constitutions are based on the Westminster system. A similar mechanism is known as parliamentary immunity.

In the United Kingdom, it allows members of the House of Lords and House of Commons to speak freely during ordinary parliamentary proceedings without fear of legal action on the grounds of slander, contempt of court or breaching the Official Secrets Act. It also means that members of Parliament cannot be arrested on civil matters for statements made or acts undertaken as an MP within the grounds of the Palace of Westminster, on the condition that such statements or acts occur as part of a proceeding in Parliament—for example, as a question to the Prime Minister in the House of Commons. This allows Members to raise questions or debate issues which could slander an individual, interfere with an ongoing court case or threaten to reveal state secrets, such as in the Zircon affair or several cases mentioned by the Labour MP Tam Dalyell.

There is no immunity from arrest on criminal grounds, nor does the civil privilege entirely extend to the devolved administrations in Scotland or Wales. A consequence of the privilege of free speech is that legislators in Westminster systems are forbidden by conventions of their House from uttering certain words, or implying that another member is lying. (See unparliamentary language.)

The rights and privileges of members are overseen by the powerful Committee on Standards and Privileges. If a member of the House is in breach of the rules then he/she can be suspended or even expelled from the House. Such past breaches have included giving false evidence before a committee of the House and the taking of bribes by members.

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