MPs have voted in favour of supporting the formation of an independent panel of experts to deal with bullying and harassment allegations against them.
The panel, made up of eight members, will have the ability to impose sanctions including suspensions and exclusions of MPs in serious cases.
It replaces the committee of MPs that currently decides on action taken.
MPs also voted to ditch plans to have debates on some panel decisions, by five votes, after concerns from staff.
The FDA union had said fear of the debates, in which MPs could have discussed the complaint in the chamber, would prevent staff from coming forward.
Amy Leversidge, assistant general secretary, said Tuesday’s vote was “an amazing result” and a “victory for all the members of staff who bravely spoke out”.
The decision follows an inquiry led by Dame Laura Cox, published in 2018, which recommended that the process to deal with bullying, harassment and sexual harassment complaints should be independent of MPs.
It was followed by other reports, including Gemma White QC’s on bullying and harassment of past and present staff of MPs, as well as MPs themselves, and an independent review of Parliament’s Independent Complaints and Grievance Scheme.
Opening the debate, Commons Leader Jacob Rees-Mogg told MPs that the behaviour of “a small number” of Members of Parliament has “disgraced and shamed” parliamentary democracy “over years and decades”.
He said the Independent Complaints and Grievance service has “already been approached by a large number of people, receiving 201 calls and emails in the first quarter of this year alone”.
Mr Rees-Mogg said it was a “really important constitutional change” that MPs were making “because of the way some honourable members have behaved and we have to stop that happening in the future”.
“As leader of this House I am ashamed when people come to see me and tell me what they have suffered, appalled at the stories that they tell me, shocked sometimes they haven’t been to the police about them they are so awful,” he said.
Mr Rees-Mogg said it was expected that the panel will be led by somebody with the standing equivalent to a High Court judge.
But several MPs spoke out against the government proposal that would have resulted in the Commons debating the most serious cases – if suspension or expulsion of an MP was involved – in the chamber.
Shadow Commons leader Valerie Vaz said this plan could result in complainants feeling too scared to come forward.
“I say to honourable members, put yourself in the shoes of the complainant and what would honourable members expect of the process?” she said.
“This way we can give a voice to the voiceless and those voices can be heard.”
Labour’s Chris Bryant, chairman of the Commons select committee on Standards, spoke in favour of his amendment – a suggested change – to the government motion which proposed ditching any debate and sending the decision straight to a vote instead.
“Many complainants fear that they would be re-victimised,” he said of the proposed inclusion of debates.
Conservative former minister Andrea Leadsom said she was planning to support Mr Bryant’s amendment.
She said the government’s proposal to enable a debate will “result in a complainant feeling re-victimised”, adding: “Therefore inevitably undermining confidence in the complaints procedure itself.”
SNP Commons leader Pete Wishart said there was “profound disappointment” among the House staff over the government’s proposal, as he raised concern over the lack of confidentiality for complainants.
And Labour MP Meg Hillier said: “I really do have concerns about a bully pulpit being used in this chamber in effect, even if people are not named, there will be gossip, there will be innuendo about who may be being referred to.”
Mr Rees-Mogg said he believed a controlled debate with clearly set out rules was preferable, adding: “But I understand that others come to a different conclusion on what is a serious level of constitutional change because of past behaviour which has besmirched the name of this House and of politics and politicians generally.”
MPs voted in favour of Mr Bryant’s amendment by 243 votes to 238. Former Prime Minister Theresa May was among 45 Conservative MPs to support it.
Amy Leversidge, assistant general secretary of the FDA Union, said: “This is an amazing result. It is truly historic for the House of Commons and a victory for all the members of staff who bravely spoke out.
“Thank you to all the MPs and especially Chris Bryant for making Dame Laura Cox’s recommendations a reality.”
Former Commons clerk Hannah White, now deputy director of the Institute for Government, tweeted: “I am so amazingly proud of the people who have stood up – at considerable personal cost – to fight for the independent bullying and harassment process that MPs today, finally, by a majority of five votes, just agreed to introduce.”
Dame Laura’s 2018 report detailed alleged sexual harassment by MPs from women who said they were “inappropriately touched” and “repeatedly propositioned”.
“Disturbing” cases were “long been tolerated and concealed”, it said, adding that senior House of Commons staff needed to make radical changes.