The Special Commission of Inquiry into LGBTIQ hate crimes is reaching the end of its probe into the investigative practices of NSW Police between 1970 and 2010.
It delved into officers' record-keeping practices and how they affected unsolved homicide cases after hearing about the mismanagement of investigations into more than two dozen gay hate deaths in Sydney.
The inquiry was shown a 2016 report that highlighted problems with the location, identification and reconciliation of exhibits relating to unsolved killings.
Detective Superintendent Daniel Doherty said he was aware of ongoing issues with tracking down exhibits and records before his promotion to lead the Homicide Squad in 2019.
He conceded the longstanding issue was "notorious" in the force and well-known among officers even when he was appointed commander.
The inquiry was told issues of poor record-keeping continued under Det Supt Doherty's leadership, with evidence not archived properly and left in various police and non-police premises with no record to indicate movement.
"The mis-labelling of records or exhibits was always an issue," Det Supt Doherty said.
"It has been a continued issue and a frustration for us."
He also admitted that while missing evidence was not an issue in a large number of unsolved homicides, there had been instances of matters not being able to progress because of the lack of records or available forensic material.
Det Supt Doherty acknowledged it was hard for officers not to be influenced by emotions when investigating certain cases, but he was confident the force remained objective in its work.
"I've seen that (objectivity) many times ... not only with the LGBTQI community, where we've dealt with victims who were murdered and resolved those matters," he said.
The inquiry will return to investigate several cases after an internal police probe examined 88 deaths, determining 27 were gay hate crimes.
Commissioner John Sackar is due to deliver his final report next month following the inquiry.