Common Informers (Parliamentary Disqualifications) Act 1975

Section 46 of the Constitution of Australia provides that if a Senator or member of the House of Representatives is constitutionally ineligible or disqualified from holding that position, they will be liable to pay any person who sues for it 100 pounds for every day that they have sat. With the introduction of the Australian dollar on 14 February 1966, where 100 pounds equaled A$200. The section has never been invoked.

Section 46 only applied "until the Parliament otherwise provides". Prompted by the case of James Webster, a Senator whose eligibility to sit was questioned in the High Court, Parliament passed the Common Informers (Parliamentary Disqualifications) Act 1975, which replaced the constitutional scheme of penalties for members sitting while ineligible. If Webster was found to have sat whilst ineligible, the penalty under the constitution may have exceeded $57,200.

Under the legislative scheme, the quantum of damages which can be recovered is significantly reduced. A person found to be ineligible is liable for a single payment of $200 for sitting in Parliament on or before the day they received notice of the suit challenging their eligibility, and a $200 payment for every day they sit in Parliament after receiving notice of the suit. A twelve-month statute of limitations has been introduced, and it is made explicit that a person may not be penalized twice for the same sitting.

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