Advances in forensic testing technology would allow those exhibits to be tested today to extract and analyse a DNA profile,Heath said,and an expert had told the inquiry semen was a “high yield” DNA source where long-term preservation was possible.

“No criticism” was made of the police officer who searched unsuccessfully for the exhibits in the present day,Heath said,but it appeared the exhibits had been lost sometime after 1982.

“Management or storage of exhibits,we submit,is ultimately the responsibility of the investigating police,” Heath said. “If a DNA profile had been recovered ... it would have provided crucial investigative leads ... and may well have held the key to identifying Mr Cuthbert’s killer.”

The systems for retaining,preserving and storing exhibits failed in Cuthbert’s case and that failure could be the cause of his murder remaining unsolved,Heath said. She said this was “unacceptable” by both contemporary and historical policing standards.

Heath said a doorman at the Midnight Shift Hotel on Oxford Street,a gay bar that has since closed,said a man matching Cuthbert’s description approached him in the hours before his death and “asked whether there were any American sailors at the bar that night”.

This was consistent with evidence that Cuthbert had recently befriended some American sailors,she said. The doorman said he replied that there were no sailors.

“According to one media article,American sailors were shown a[1980] movie called Cruising on board a naval vessel docked in Sydney on the very night of Mr Cuthbert’s murder,” Heath said.

The film depicted the murders of gay men by a psychotic killer and provoked outrage in the gay community at the time,she said.

“Whether it’s true that this movie was shown on board a naval ship could not be ascertained. Police did make inquiries as to the naval ships that were docked but were advised that they had already departed from Sydney at the time of those inquiries.

“They were further advised that no records were kept of the sailors taking shore leave. I note that there was no investigation as to the type of combat knife that was ordinarily carried by American sailors and further whether they were permitted to carry those knives with them on shore leave.”

Heath said the inquiry may in the future consider “global recommendations” about the “retention,preservation and storage of exhibits”.

The inquiry continues.

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