This file photo taken on March 22, 2020 shows Australia's Prime Minister Scott Morrison reacting during a press conference at Australia's Parliament House in Canberra. (DAVID GRAY / AFP)

CANBERRA - The head of the Australian Federal Police (AFP) has written to Prime Minister Scott Morrison, warning him about politicians delaying reporting criminal conduct.

Reece Kershaw, the Commissioner of the AFP, wrote to Morrison after Home Affairs Minister Peter Dutton became the third minister to reveal that he knew about allegations that former government adviser Brittany Higgins was raped in Parliament House before the PM.

The process for reporting crimes in parliament has come under severe scrutiny since former government adviser Brittany Higgins went public with allegations that she was raped by a colleague in the office of Defense Minister Linda Reynolds in March 2019

The process for reporting crimes in parliament has come under severe scrutiny since Higgins went public with allegations that she was raped by a colleague in the office of Defense Minister Linda Reynolds in March 2019.

Kershaw said in his letter that delays in reporting crimes could damage investigations.

"I cannot state strongly enough the importance of timely referrals of allegations of criminal conduct," he wrote, according to News Corp Australia.

"Failure to report alleged criminal behaviour in this manner, or choosing to communicate or disseminate allegations via other means, such as through the media or third parties, risks prejudicing any subsequent police investigation.

"Any delay in reporting criminal conduct can result in the loss of key evidence, continuation of the offending and/or reoffending by the alleged perpetrator."

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In addition to Dutton and Reynolds, Employment Minister Michaelia Cash, Senate President Scott Ryan and House Speaker Tony Smith knew about the alleged 2019 rape before Morrison.

Morrison on Thursday wrote to Ryan and Smith asking that Kershaw's advice be forwarded to all federal politicians.

"The events of the past fortnight have demonstrated again why it is so important that all members and senators are informed of their responsibilities in these situations, both to provide compassionate support to those who are affected and to ensure that we uphold the rule of law in dealing with these issues," he said. 

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