MPs and peers could face recall or expulsion under new sanctions for bullying and abuse recommended in a report which found evidence of widespread allegations of sexual harassment within Parliament.
A survey of 1,377 parliamentary workers found that almost one in five (19%) said they had experienced or witnessed sexual harassment or inappropriate behaviour over the past year - with twice as many female as male complainants.
And 39% of respondents reported experience of non-sexual harassment or bullying over the same period, including 45% of women and 35% of men.
The report, by a cross-party working group chaired by Leader of the Commons Andrea Leadsom, recommended the creation of a procedure for complaints and grievances that will be "independent from the political parties, and offer confidentiality and fairness to those who have a complaint brought against them".
It called for a review of existing Codes of Conduct to reflect a new Parliament-wide Behaviour Code.
Under the proposed system, complaints would spark a confidential inquiry by the Parliamentary Commissioner for Standards, with a tougher range of sanctions for those found to have behaved inappropriately.
On receiving the Commissioner's report, standards committees in the Commons and Lords would be able to recommend the suspension of an MP or peer for a specified period.
This could trigger proceedings for recall of an MP - resulting in a new election in his or her constituency - or the expulsion of a peer.
The survey found that a quarter (24%) of those who had experienced inappropriate behaviour in the past 12 months spoke to their MP or line manager.
But only half of staff had confidence in the system for managing complaints of bullying and harassment.
The report recommended that the new Behaviour Code should be binding on to all those working in or for Parliament and its members, providing a basis for "significant and sustainable change".
"The evidence, particularly from staff, was that a change in workplace culture is both urgent and essential, and is ultimately the best guarantor of a change in behaviour," said the report.
"It is unacceptable that inappropriate behaviours, including bullying and harassment and sexual harassment, take place across what we have called 'the parliamentary community'.
"The Working Group recognises that a greater understanding of these issues will be an important contributor to change, so there is a need for mandatory and voluntary training for MPs, peers and staff."
The report warned that care must be taken to ensure that MPs do not have their reputations wrongly destroyed by false complaints.
"It is recognised that parliamentarians are under a constant media spotlight and that, due to the nature of political discourse, there is a risk of malicious and/or vexatious complaints against those who work in the Palace of Westminster either as MPs, peers or staff," it said.
"The new procedures must ensure checks and balances are in place to guard against such complaints.
"At the same time, the new scheme must put arrangements in place to minimise the well-documented risk of under-reporting by those experiencing sexual or other forms of harassment or bullying."
Unveiling the report, Ms Leadsom said: "This is a big day for Parliament and our politics. The new independent procedure will demonstrate that we want to be the best parliament in the world when it comes to treating everyone who works here with dignity and respect.
"This is a major step in bringing about the culture change that Parliament needs."
Georgina Kester, who represented the Members and Peers' Staff Association on the Working Group, said: "Having called for this action for many years, MAPSA welcomes and endorses the report and the proposals contained within it, which will go a long way to combating the bullying and harassment that staff have experienced.
"We look forward to staff being fully involved in the next stages of the rollout of the disciplinary processes, sanctions, training and support mechanisms."
The Working Group's report will be considered by both Houses, with a debate due to take place in the two weeks, after MPs return from their half-term recess on February 20.