The GMB union has called on Labour's executive to deselect MPs found guilty of unjustified expense claims.
The trade union, which represents manual workers and the health service, said there was no excuse for MPs not to have used moral judgement when claiming expenses and those who refused to do so should not have a seat in Parliament.
It has called on Labour's National Exeuctive Committee (NEC), which meets today, to outline action to remove MPs found guilty of misconduct from office.
Speaking yesterday, Paul Kenny, the GMB general secretary, said: "Those who have failed to exercise this moral judgment have no place in Parliament representing the Labour Party."
He added: "GMB members want the NEC to outline the process that will be used to deselect these MPs as candidates for the Labour Party for the next General Election."
Unjustified expense claims included MPs claiming thousands of pounds worth of mortgages that had already been paid off, a claim for a second home allowance totalling thousands of pounds before the MP had been elected, as well as more mundane items like dog food and horse manure.