Senator Jacqui Lambie wants Prime Minister Malcolm Turnbull to investigate claims the navy failed to take action over an alleged rape of a junior sailor by a higher ranked sailor.
Alleged victim, former sailor Trent Bourne, says his attempts to report the abuse through the chain of command were fobbed off and he has letters, emails and medical notes to support his claims.
"I am utterly appalled that his allegations of sexual abuse have not been taken seriously or dealt with accordingly," Senator Lambie said in a letter to the PM, as well as the defence and veterans' affairs ministers.
"This occurred in 2012 and it still has not been resolved."
The latest allegations arise with the Australian Defence Force (ADF) having battled a culture of abuse in its ranks for several years.
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Senator Lambie met with the Prime Minister in February over accusations the ADF had ignored the abuse, including sexual assault, of an SAS trooper and former Army officer.
A letter from former Deputy Chief of Navy Michael Julian van Balen sent on March 28, 2014 to Mr Bourne confirms former Chief of Defence Force David Hurley was made aware in 2013 of the alleged attack.
Emails between Mr Bourne and the Inspector-General of the Australian Defence Force (IGADF) - which independently monitors the military justice system - confirm an investigation was launched in January, 2016 into the alleged attack and claims the ADF failed to act.
Mr Bourne said the alleged attack took place in late January 2012 when he was invited to the off-base apartment of the senior sailor after a group meeting which they both attended.
"He went to the bathroom, came out with no shirt on and grabbed me and pushed me with force into the bedroom," he said of the alleged rape.
A spokesperson for the ADF said all allegations of inappropriate or potentially criminal behaviour by Defence personnel were taken very seriously.
"Primary responsibility for the investigation of criminal allegations does, however, lie with the civilian police even in cases involving ADF personnel," the defence spokesperson said.
