Craig Thomson faces jail time and a $5000 fine for allegedly deliberately misleading Parliament after Labor backed an Abbott government push to refer him to the privileges committee.
This would be on top of a possible five-year jail term for misusing union funds to pay for prostitutes and other services. A court last week found Thomson guilty of defrauding the Health Services Union while he was its national secretary.
On Monday, Speaker Bronwyn Bishop instructed the privileges committee to investigate whether Thomson misled Parliament in a speech in May 2012 in which he vehemently denied misusing his union credit card. He claimed in the speech he had been set up by rivals in the HSU.
A previous privileges committee investigation into Thomson was put on hold pending the outcome of his court case, and lapsed with last year's election.
The motion to refer the matter again to the committee was introduced by Liberal backbencher Karen McNamara and backed by Labor, even though Labor has labelled the move a ''stunt''.
''As we supported it in the last Parliament, we support the reference in this Parliament,'' opposition business manager Tony Burke said.
The leader of the House of Representatives Christopher Pyne said: ''Telling the truth in Parliament is an extremely important aspect of the role we play as members of Parliament.
''Sure, politicians have been accused over the centuries of sometimes gilding the lily and perhaps not being entirely fulsome with all aspects of the truth.
''But that is a far cry from standing up in the Parliament and making statements which are deliberately misleading, which are lies.''
The House of Representatives can impose jail terms of up to six months and fines of up to $5000 for misleading Parliament. It can also issue public reprimands and request an apology.
