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The privilege of peerage is the body of special privileges belonging to members of the British peerage. It is distinct from parliamentary privilege, which applies only to those peers serving in the House of Lords and the members of the House of Commons, while Parliament is in session and forty days before and after a Parliamentary session.

The privileges have been lost and eroded over time. Only three survived into the 20th century: the right to be tried by other peers of the realm instead of juries of commoners, freedom from arrest in civil (but not criminal) cases, and access to the Sovereign to advise him or her on matters of state. The right to be tried by other peers was abolished in 1948. Legal opinion considers the right of freedom from arrest as extremely limited in application, if at all. The remaining privilege is not exercised and was recommended for formal abolition in 1999, but has never been formally revoked.

Peers also have several other rights not formally part of the privilege of peerage. For example, they are entitled to use coronets and supporters on their achievements of arms.

The privilege of peerage extends to all temporal peers and peeresses regardless of their position in relation to the House of Lords. The right to sit in the House is separate from the privilege, and is held by only some peers (see History of reform of the House of Lords). Scottish peers from the Acts of Union 1707 and Irish peers from the Act of Union 1800, therefore, have the privilege of peerage. From 1800, Irish peers have had the right to stand for election to the United Kingdom House of Commons but they lose the privilege of peerage for the duration of their service in the lower House. Since 1999, hereditary peers of England, Scotland, Great Britain, and the United Kingdom who are not members of the House of Lords may stand for election to the House of Commons. Their privilege of peerage is not explicitly lost by service in the lower House. Any peer issuing a disclaimer under the provisions of the Peerage Act 1963 loses all privileges of peerage. The privilege of peerage also extends to wives and widows of peers. A peeress by marriage loses the privilege upon marrying a commoner, but a peeress suo jure does not. Individuals who hold courtesy titles, however, do not have such privileges by virtue of those titles. Lords Spiritual (the 26 Archbishops and Bishops who sit in the House of Lords) do not have the privilege of peerage as, at least since 1621, they have been Lords of Parliament, and not peers.

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Wikipedia