DUP's Jim Shannon votes to give MPs facing investigation anonymity
A DUP man was among 79 who voted to grant Members of Parliament anonymity if accused of sexual harassment or expenses fraud.
The probe that resulted in Ian Paisley being banned from the House of Commons would have been kept secret under the new code of conduct passed on Thursday.
MPs agreed new rules aimed at clamping down on bullying and harassment, but it also ends the power to name MPs and peers accused of offences over expenses or conflicts of interest.
The vote to give anonymity to those under investigation came just a day after Mr Paisley was hit with a 30-day suspension for breaking Westminster rules over well-publicised luxury trips to Sri Lanka for him and his family worth up to £100,000.
Labour MP Sir Kevin Barron had attempted to change the code in order to remove the provision for confidentiality, but his amendment was defeated 79 votes to 22. The DUP's Jim Shannon was among those voting against the amendment.
Since 2010 the Parliamentary Commissioner for Standards has listed all MPs under inquiry on its website and rulings are also automatically published, but the new behaviour code ends this transparency.
Sinn Fein slammed the move, with the party saying: "We are not surprised that Westminster has moved to roll back transparency when it comes to MP misconduct.
"Only this week we've seen Ian Paisley receive a 30-day suspension.
"This regressive step is consistent with the Westminster culture of cover-up that many in the north of Ireland will be all too familiar with. This is a case of the British Establishment protecting itself from scrutiny that applies to other citizens."
Commons Leader Andrea Leadsom told MPs: "We're proposing that the Commissioners of both Houses will keep their investigations entirely confidential until such time as there is a finding. This is crucial if individuals are to place their trust in the new system.
"There is clearly a balance to be struck between the public interest in transparency and putting the complainant at the heart of the process by protecting their identity. That is absolutely vital."
But MPs on the cross-party Committee on Standards argued MPs should not have anonymity over accusations of fiddling expenses or conflicts of interest. Committee chairman Sir Kevin said the new code was "a step backwards".
All information about two current high-profile investigations into two MPs - Labour's Keith Vaz and Conservative Robert Courts - has now vanished.
The DUP and Mr Shannon didn't comment.
The suspension on Mr Paisley was imposed after he took his family on two holidays to Sri Lanka in 2013 paid for by the Sri Lankan government.
The MP failed to register the trips before writing to Prime Minister David Cameron in support of the Sri Lankan government "about a proposed United Nations resolution".
The punishment also exposes Mr Paisley to the danger of being "recalled" by his constituents under legislation passed in 2015, which would trigger a by-election. If a recall petition is opened, it must be signed by at least 10% of the electorate in his North Antrim constituency for a vote to take place.
The lengthy suspension, to begin on September 4, also reduces Prime Minister Theresa May's effective working majority by one ahead of more potentially crucial Brexit votes in the autumn.