Four New South Wales police officers who were investigated in an undercover sting operation last year have requested access to the investigation file, saying they were targeted because of their sexuality.

The six-month covert investigation, code named "Andro," was originally assembled to investigate "illicit drug use" within the department but wound up focusing solely on the three gay officers and one of their longtime partners: Christian McDonald, Christopher Sheehy, Shane Housego and Steven Rapisarda.

During that time the officers received "random" drug tests, were tailed by undercover officers conducting surveillance in bars they "regularly visited," and were studied by behavioral psychologists who compiled intelligence files on each, according to the Sydney Morning Herald.

"Our clients say they were covertly monitored and targeted for drug testing purely because they identify as homosexual," said Nicholas Stewart, an attorney representing the group. "They seek documents that they believe will evidence a discriminatory motivation by NSW Police."

The investigation, the men claim, was part of a culture of "homophobic prejudice" within the NSW police department.

"Common terminology and phrases used around the station are faggot, poofter, gay as aids, homo, hommus and eat a dick," Sheehy said in a complaint.

"I have heard a lot of homophobic, negative and derogatory comments made by police officers, particularly among senior officers in management positions ... I do not feel I have been able to report them due to fear of repercussion."

In a separate complain, McDonald claimed he once requested to work security for a music festival called "Splendour in the grass," to which his manager replied: "Splendour in your ass."

"In 2013, I fell over in the dark on the way to work and was knocked unconscious as a result of hitting my head on a pavement," McDonald recalled of another incident. Upon returning to work, he was approached by a manager who told him, "You should be used to having your head down, arse up in the concrete."

Rapisarda added that he's "concerned about the extent to which public resources were used in pursuit of an investigation ... which was based solely on my sexual orientation."

The New South Wales police have refused to turn over the investigation files pending "legal proceedings," but confirmed in a statement Saturday that it has a "zero tolerance" policy.