Parliament is dealing with a “permanent swamp” of complaints and concerns about MPs’ conduct, Penny Mordaunt said as she outlined proposed reforms to the Commons.

MPs could be prevented from entering Parliament if they are under investigation by police for “credible allegations of sexual or violent offending”, according to the proposals.

The House of Commons Commission report states the MP could face a risk assessment to judge whether they pose a threat to others working on the parliamentary estate.

An “adjudication panel” consisting of senior parliamentarians would then make a decision if there is a recommendation for exclusion, which would automatically end once the matter has been concluded.

Commons Leader Ms Mordaunt said there are more than 12 different bodies who oversee the conduct of MPs, telling the House: “We have this incredibly complicated standards landscape, a myriad of bodies that are forming oversight of members’ conduct and yet barely a week goes by without something happening that calls into question our adherence to those rules.

“We seem to remain in a permanent swamp of complaints, cases and concerns, and the need for professionalism and the need to build trust has never been greater.

“It is therefore vital that as well as the minutiae of schemes and reports, we also focus on the principles that should govern our behaviour and the culture, and, crucially, duty of care we have to one another in this place, and the duty we have to protect the good functioning of democracy.”

Conservative former minister Sir Jacob Rees-Mogg earlier voiced concerns over the proposed process, saying: “There is nobody that can suspend a member from this House without a vote of this House.

“The constitutional problem with the proposals before us today is that they would allow a suspension by bureaucracy rather than by democracy of this House.”

Ms Mordaunt, in her reply, said: “No rule that we will make in this place will be arrived at without the consensus of the House and will of the House.”

DUP MP Jim Shannon (Strangford) said: “I am always reminded that you’re innocent until proven guilty, and I just want to ask this question to the Leader of the House because it seems to me that what I see looking from the outside in (is) that now you’re guilty, now prove your innocence – surely that’s against the law of the land in its entirety?”

Ms Mordaunt replied: “I completely agree with (Mr Shannon) on that point and this is a very narrow set of circumstances, and it’s not about asking people to make a judgment on whether someone has committed an offence or not, it’s not about that. It’s about the risk an individual poses to other people.”

Conservative MP Nickie Aiken, a member of the House of Commons Commission, said: “As a House of Commons Commission, we do have a duty of care to the thousands of members of staff who work in this estate.”

Conservative former party leader Sir Iain Duncan Smith said: “We have to be really, really careful here because reputational damage is the end to Members of Parliament and often cannot be regained – your character is all.

“So, the point really here is, how do we protect that if people are then going to be sent away? How can they not do the work in their constituencies and still retain their reputation as being Members of Parliament?”

Ms Mordaunt said: “There are members that are off the estate for various reasons on a voluntary basis currently, I feel very strongly that in those circumstances, particularly when as we all know investigations are taking a long period of time, that their ability to represent their constituencies is not compromised.”

Shadow Commons leader Thangam Debbonaire said: “This is not a replacement for the criminal justice system, it is not a parallel system … but we need to find a way to take on board when there is a criminal justice system investigation of a very serious crime, how we mitigate those risks in a … time-limited way.”