MPs refused to back a key recommendation in 2012 to broaden the remit of the parliamentary standards watchdog which would have helped it investigate sexual harassment claims.
The cross-party standards committee recommended that the code of conduct should be widened to cover MPs who bring parliament into disrepute through behaviour in their "private and personal lives".
But Conservative, Labour and Liberal Democrat MPs joined forces to block this by backing an amendment, tabled by Tory MP Charles Walker, amid fears that the new rules would be too intrusive.
In light of recent reports of sexual misconduct by MPs, standards committee chair Kevin Barron believes parliament now needs to look again at the code of conduct.
On Monday, MPs spent over an hour debating sexual harassment in Westminster, as pressure mounted on party leaders to get a grip on the problem once and for all.
MPs spoke of staff who had been sexually assaulted, with no action taken; of researchers been made to feel "deeply uncomfortable" in a Commons bar; and of "systemic" bullying by some MPs.
In the debate, Barron said: "Much has been made in the media this weekend of the inability of the standards commissioner, and therefore the standards committee, to look into many of the issues raised over the past week.
"In a report debated in March 2012, the committee tried to give the commissioner a wider scope over these issues, but an amendment tabled by the three major parties’ parliamentary shop stewards and supported by frontbenchers was introduced to block this, and therefore the commissioner was left unable to look into these very important issues.
"When the standards committee re-forms shortly, we will again look at the code of conduct, and I hope that all parties represented here will be a lot more receptive to necessary changes."
In the debate in 2012, Barron appealed to the House of Commons to back a motion on a revised code of conduct for MPs – to make sure the standards commissioner had enough powers to investigate MPs who damage the reputation of parliament through behaviour in their private lives.
The existing code of conduct states that it "does not seek to regulate what members do in their purely private and personal lives".
But the commissioner and committee said this sentence should be added: "unless such conduct significantly damages the reputation and integrity of the House of Commons as a whole or of its members generally".
MPs at the time were overwhelmingly opposed to this change. Tory MP Charles Walker said the move would give the commissioner "almost unlimited scope" to investigate anything.
He said in the 2012 debate: "I worry about where this new activism by the commissioner might lead. Over the weekend, I racked my brain to try and imagine scenarios in members’ private lives that would trigger the interest of the commissioner, and I could only come up with two topics: the bedroom and the bottle.
"In common with most people, these are the two weaknesses that seem most likely to compromise members of parliament in their private lives."
Labour's Angela Eagle, then shadow Commons leader, described it as "mission creep" and warned the code of conduct could become a "code of morals".
But Barron pleaded with MPs to back his motion, saying: "This is not about morals ... There are circumstances and occasions on which members have gone overboard but have not been covered by the code."
Instead the Commons backed an amendment tabled by Walker which barred the commissioner from investigating anything solely related to the "conduct of an member in their private and personal lives".
An ally of Barron told BuzzFeed News on Tuesday that the standards committee had long planned a fresh review of the MPs' code of conduct, which will take place in the coming weeks and take into account the latest harassment allegations.
They said that widening the scope of investigations by the standards commissioner would "certainly help" deal with sexual harassment allegations in parliament.
Emily Ashton is a senior political correspondent for BuzzFeed News and is based in London.
Contact Emily Ashton at firstname.lastname@example.org.
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