The House of Representatives has the power to imprison for up to six months an individual found to be in contempt of Parliament by the privileges committee, and it’s a punishment they’ve doled out before.

Independent MP Craig Thomson and Liberal backbencher Craig Kelly have been referred to the Standing Committee of Privileges and Members’ Interests this week.

In 1955, two members of the public — newspaper editor Frank Browne and newspaper owner Raymond Fitzpatrick — were jailed for three months by Parliament for breaching parliamentary privilege rules when their newspaper The Bankstown Observer impugned MP Charles Morgan.

The Committee of Privileges, as it was then known, found the men tried to influence Morgan’s conduct in Parliament when they published an article that said Morgan had been involved with an “immigration racket” by taking money from prospective immigrants in exchange for helping them jump the queue.

While it’s unlikely the Parliament would jail Thomson or Kelly, it is within the realms of possibility, assuming such a punishment was supported by a majority in the House when put to a vote.

The Coalition moved a motion this week to bring Thomson before the privileges committee for misleading the Parliament. The move was backed by the Labor government, while Labor has also moved to bring Kelly before the committee for failing to declare his directorship of some companies. It has also been reported that the government will move to bring Liberal frontbencher Sophie Mirabella before the committee for failing to declare financial interests.

Under the Parliamentary Privileges Act 1987 the House also holds the power to impose a fine of up to $5000 on an individual or suspend a member from Parliament if the 11-member committee, chaired by Labor MP Yvette D’Ath, finds against that person.

Only four Liberal members sit on the House privileges committee, compared to six Labor MPs (including the chair) and independent Tony Windsor, although traditionally members of the committee do not act on party lines.

The committee usually sits in private and has the power to call witnesses to come before it and to compel required documents to be presented. Witnesses may be asked to make an oath before providing evidence.