An inquiry into defence and veteran suicide has heard of a steady decline in abuse reports within the ADF over 50 years, although there still needs to be a "circuit breaker" to stop a culture of bullying and harassment.
Leonard Roberts-Smith on Tuesday told the commission recruits lodging complaints with the Defence Abuse Response Taskforce felt "betrayed" and "let down" by the ADF over historic abuse suffered in training bases.
Mr Roberts-Smith formerly chaired DART to assist complainants who had suffered sexual and physical mistreatment, and workplace harassment, in Defence prior to April 2011.
He told the commission on Wednesday reported sexual abuse, harassment and bullying had declined across the Navy, Air Force and Army since the late 1970s.
However during examination he agreed with Peter Gray QC that data indicated sexual abuse was still prevalent in the Navy between 2000-2009 despite decreasing across other services.
"The Navy was the service relating to which we received the highest proportion of complaints," Mr Roberts-Smith said.
It had disproportionately accounted for 41 per cent of all cases of sexual abuse despite making up roughly 25 per cent of the forces in total.
Navy sexual abuse reports were at their highest in the 1970's, with the Army and Airforce experiencing their peaks between 1980-1989.
Bullying and harassment within the Army was most heavily reported also during the 80s, but the following two decades it recorded only minor decreases.
Mr Roberts-Smith said there was hierarchical and authoritative exploitation across training institutions like the Naval base HMAS Leuuwin and ADFA where alleged abuse of authority was committed by staff.
"We had complainants who were being sexually assaulted by the captain of the ship, or the executive officer or in the army by a colonel ... and it was quite common for junior soldiers to be assaulted or abused in one form or another by the junior non-commission officer."
Commissioner Dr Peggy Brown put to Mr Roberts-Smith that it was hard not to think there was just a "fundamental failure by Defence to protect these people".
"That is the obvious conclusion that is reflected in our report in those particular cases," he replied.
Then asked of the potential continuing implications of the closed nature of the ADF, Mr Roberts-Smith said: "The potential continuing ramifications are that the cycle continues.
"There has to be a circuit breaker."
Australian Associated Press
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