Scott Morrison has again ruled out calling an independent inquiry into rape allegations against Attorney-General Christian Porter.
The prime minister continues to argue the allegations should be dealt with through the police and the courts.
"I see no justification for any extrajudicial inquiry that might be set up by a prime minister or any other politician," he said on Tuesday.
"We have competent and authorised agencies to deal with these matters both through the police and the courts, and that is where I will make my assessments of those matters. That is where it should be done."
Mr Porter has taken indefinite leave after vehemently denying he raped the woman more than 30 years ago.
Asked whether he believed the denial, Mr Morrison said he believed in the presumption of innocence and the rule of law.
"There are not two rules, there are not two laws in this country, there are not two processes, there is one and we are all subject to it," the prime minister said.
"I'm not going to indulge in other extrajudicial processes that suggest that one Australian is subject to a different legal process to any other Australian.
"If we do that, we are eroding the very principles of the rule of law in this country. So, there are not two laws in this country and I won't allow that to be eroded."
The woman who made the claim took her own life last year after telling police she did not want to proceed with her complaint.
Employment Minister Michaelia Cash, who is filling in for Mr Porter, says the rape allegations against him should not be investigated further.
"Once the police have closed an issue like this, that is actually where the matter stops," Senator Cash told Nine.
"The NSW Police have made it very clear - the matter is closed. They are not pursuing it any further."
Former cabinet minister Julie Bishop says the next logical step is a coronial inquest.
"It's within the criminal justice system. There are checks and balances and there are statutory powers. It has legal standing," she told the ABC.
"And so, that is the next step and I understand from media reporting that's what the family would welcome."
Mr Morrison and his cabinet colleagues are open to a coronial inquest.
But his predecessor Malcolm Turnbull said an independent inquiry would be in the best interest of Mr Porter.
"That would enable there to be a process which would enable the issue to be resolved. The problem is it remains unresolved in the minds of many people," Mr Turnbull said.
Fellow former prime minister Kevin Rudd is also calling for an independent inquiry into the rape allegations.
Mr Rudd said the judicial inquiry should be short in duration and "quite focused" in its terms of reference.
"I think that the appropriate course of action under these circumstances is for that to occur," he told the National Press Club in Canberra.
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