A confidential inquiry has been launched into legal issues around Parliament House access following rape allegations raised by Brittany Higgins.

Ms Higgins alleges she was raped by a colleague inside a ministerial office in 2019 after the pair were granted access to the building after hours.

The alleged perpetrator was sacked for a security breach linked to the alleged sexual assault.

The Greens have been pursuing the government over whether the man has ever been signed into parliament following the incident.

A confidential inquiry has now been launched to investigate legal issues around publishing names linked to people signed into the building.

House of Representatives Speaker Tony Smith and Senate President Scott Ryan said security had an overriding responsibility to uphold parliamentary privilege.

Parliament’s presiding officers said publishing details of politician or staff member signing a person into the building may prompt questions about privilege.

Greens Senate leader Larissa Waters said it was deeply inappropriate for the matter to be scrutinised in private.

“It looks an awful lot like sweeping this under the carpet and sending it to a committee that is not conducted in public and presumably can’t be spoken about,” she told the upper house on Wednesday.

Senator Ryan was caught off guard by the criticism.

“I wasn’t aware you were going to make those particular comments that, in my view, unfairly impugn my motive or actions over the past few weeks,” he said.

“I do reject the motives or implications that you said in your statement, given at all times with respect to you and your questions I have acted in good faith.”

Senator Ryan said he was still seeking details of any event the accused man could have been signed in for.

He said he was bound to act under parliament’s rules, which meant he could not unilaterally make decisions about releasing the information.

Government upper house leader Simon Birmingham said he understood Senator Waters’ concerns but also noted the presiding officers were following the rules.

“We have to date provided as much information as is actually available in relation to passes, in relation to access, and we will continue to do so,” he said.

Asked by Greens leader Adam Bandt in parliament whether the alleged rapist had met with ministers or staff at any time after the incident, Prime Minister Scott Morrison said: “The scale of what the member is asking is not something that we can give a definite response to.”

“We have looked into this matter and I have no information to suggest what that what the member suggests is true,” he said.

-AAP