Disgraced MP Derek Conway was today suspended from the Commons for 10 days and ordered to repay up to £13,161 improperly paid to his son Freddie.
MPs endorsed the recommendations of the Standards and Privileges Committee without a vote, after a 35 minute debate.
Mr Conway was not in the chamber to hear discussion of his case.
Labour MP Frank Field questioned whether his punishment was adequate.
He told MPs: "If this example of what I would see as embezzlement had occurred in the refreshment department on this scale, we would have expected that person to leave the employment of this establishment on that day.
"I believe we should treat ourselves in a similar manner."
The suspension of the Old Bexley and Sidcup MP came as Downing Street backed calls for greater transparency in the way MPs claim expenses and allowances.
Repeated attempts in the past to force disclosure of the names of MPs' staff have been blocked.
Prime Minister Gordon Brown backed calls from Justice Secretary Jack Straw that there should be more openness with the public about where the allowances are spent.
But he stopped short of backing specific proposals to name all MPs' staff.
Mr Brown's spokesman said today: "The Prime Minister agrees with Jack Straw that there should be greater transparency over MPs' expenses.
"Exactly how this should be achieved is, of course, a matter for the House authorities to consider."
During a visit to Wandsworth Prison today Mr Straw said: "I've never understood for the life of me why MPs are not required to say who they employ."
He said many MPs employed spouses or children who worked "very hard" for them.
But he added: "What's important is the public should know about this.
"After all, we are spending public money on providing a public service. Of course people should know."
His comments come after Sir Christopher Kelly, chairman of the Committee on Standards in Public Life, called yesterday for more transparency in MPs' use of allowances.
The Justice Secretary added that it was "infuriating" for the vast majority of MPs when their reputations were tarnished by a small minority.
In the next few weeks MPs may consider proposals for the National Audit Office to make spot checks on a random sample of MPs' expense and allowances claims.
Liberal Democrat Simon Hughes said today he would back that proposal.
Mr Conway, who has had the Tory whip withdrawn from him and has announced he is to step down at the next election, today hit back at media coverage of his affairs, including photos of his sons Freddie and Henry partying.
He has been accused of paying both sons public money for doing little or no work and was under renewed fire after it emerged that one of his son's friends Michel Pratte had also been on his payroll.
Leaving his central London mansion flat, the MP, who also faces a possible police probe into the payments to his sons, pointed out that Mr Pratte was not a relative.
He also defended his sons, who were pictured in one newspaper today partying.
He said: "Young people will be young people".
He added: "They have a right to a social life."