Parliamentary privilege is a term used to describe the various rights, powers and immunities of parliament, its members and committees. They include:
o the right to free speech in Parliament, without the threat of being sued for defamation for any statements made when in Parliament or being questioned in a Court or Royal Commission for any statements made in parliament or incurring any legal liability for anything said in parliament;
o immunity of members from molestation and arrest and imprisonment for civil causes while attending Parliament; and
o immunity of Parliamentary witnesses from being questioned about or impeached for evidence given before either House or its Committees.
It is asserted that without its privileges, Parliament and its Members could not function properly. This view has prevailed since the earliest days of Parliament, long before the establishment of the Western Australian Parliament. It arose from the struggle waged by the House of Commons to establish it authority relative to the Crown. The struggle was resolved in the United Kingdom after much conflict, with the passage of the Bill of Rights 1689.
The immunities and powers conferred by parliamentary privilege were considered fundamental in Western Australia at the time of self-government and were written into s.36 of the Constitution Act 1889.(21) In 1891 the Western Australian Parliament enacted the Parliamentary Privileges Act. It is through that Act that article 9 of the Bill of Rights came to apply to our system of government.(22) Other legislation which is relevant to the immunities of Parliament and its Members includes the Parliamentary Papers Act 1891(23) and s.351 of the Criminal Code.(24)
A constitutional change in November 2004 has linked the scope of parliamentary privilege in Western Australia to that enjoyed by the United Kingdom House of Commons as at 1989.