Parliamentary immunity

Parliamentary immunity, also known as legislative immunity, is a system in which members of the parliament or legislature are granted partial immunity from prosecution. Before prosecuting, it is necessary that the immunity be removed, usually by a superior court of justice or by the parliament itself. This reduces the possibility of pressing a member of the parliament to change his or her vote by fear of prosecution.

Legislators in countries using the Westminster system, such as the United Kingdom, are protected from civil action for slander and libel by parliamentary immunity whilst they are in the House. This protection is part of the privileges afforded the Houses of Parliament under the Common Law (parliamentary privilege). Parliamentary immunity from criminal prosecution is not enjoyed by Members of Parliament under the Westminster system. This lack of criminal immunity is derived from the key tenet of the British Constitution that all are equal before the law.

In the run-up to the 2006 election in Canada, Conservative Party leader Stephen Harper denounced the ruling Liberal Party on the floor of the House of Commons, contending that the government ran "a massive corruption ring using organized crime to defraud taxpayers." Although the Liberal Party had threatened to sue Harper if he repeats his allegation during the campaign, parliamentary immunity prevented them from legal action against his statements in the Commons.

The 1988 Brazilian constitution grants parliamentary immunity to members of both the Chamber of Deputies and the Senate. Unlike other countries, Brazilian parliamentary immunity is also extended to crimes committed outside a parliamentarian's official duties (murder, theft, etc.). This does not apply for crimes committed before the member of parliament takes office. Members of parliament can be arrested only for crimes if caught at the time of the criminal act in flagrante for a crime with no possibility of bail. These arrests can be overruled by a floor vote of the particular parliament chamber that parliamentarian belongs to.

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