If so, it appears Mr. Johnson may not have been the only one.

During the 1980s and 1990s, the Australian authorities now say, gangs of teenagers in Sydney hunted gay men for sport, sometimes forcing them off the cliffs to their deaths. But the police, many of whom had a reputation for hostility toward gay men, often carried out perfunctory investigations that overlooked the possibility of homicide, former officials and police officers say.

Now the police in New South Wales, the state that includes Sydney, are reviewing the deaths of 88 men between 1976 and 2000 to determine whether they should be classified as anti-gay hate crimes.

About 30 of the cases remain unsolved, and the police have not said how many of the killings were tied to gangs. About a dozen victims were found dead at the bottom of cliffs or in the sea, the police say.

The review and the inquest into Mr. Johnson’s death are casting light on a shocking chapter of Sydney’s history, one that some say has yet to be fully revealed.

“We can now see that predators were attacking gay men,” said Ted Pickering, who was the police minister for New South Wales in the late 1980s. “And they were doing it with the almost-certain knowledge that the police would not have gone after them. That was the police culture of the day.”