What these crimes all had in common was the type of victims: gay men. Most of the assaults were premeditated. These were gay bashings. When this wave of crime washed through Sydney between 1985 and 1999 the phenomenon was largely invisible to the wider culture. About 20 deaths officially recorded during this time as unsolved, suicide or death by misadventure are now seen to fit a pattern of gay-hate murder that has never been officially acknowledged. The number of serious assaults, enough to require hospitalisation, was in the hundreds during these years. Most were never categorised as gay-hate crimes. The number of violent incidents numbered in the thousands. Few perpetrators were charged. Sue Thompson, a former long-time gay and lesbian client consultant to the NSW Police, has estimated that between 1989 and 1999 there were 46 gay-hate murders in NSW. This assessment is supported by a study published more than a decade ago, ''Hatred, Murder and Male Honour'', by a criminologist, Stephen Tomsen, published in 2002 by the Australian Institute of Criminology. Tomsen concluded there were about 50 gay-hate murders in NSW between 1985 and 1995.

Both these estimates now appear to understate the problem. They were based on reported homicides, not cases of suicide or misadventure, some of which were almost certainly wrong. ''There's no way of knowing, yet, just how many people were murdered, or seriously assaulted, but I have no problem with using the word ''thousands'' to describe the scale of the violent incidents during that time,'' Daniel Glick, an American investigative reporter, told me. Glick spent months investigating gay-hate crime in Sydney at the behest and cost of Steve Johnson, an American high-tech entrepreneur whose brother Scott was found dead in Manly in 1988. The first sign that something was badly amiss with police investigations - a warning that would not be understood for many years - was a small item in The Manly Daily published on December 11, 1988: ''The body of a young man was found at the foot of North Head on Saturday. He was Scott Russell Johnson, a Californian student who had been staying in Canberra recently. The body was found among rocks about 200 metres north of Blue Fish Point and police believe he had been dead for several days. There were no suspicious circumstances according to police.''

There were, in fact, multiple suspicious circumstances. Johnson's body was found naked. The area was well known as a popular gay beat, or pick-up area. The victim had shown no signs of distress or isolation. Other gay men had been bashed in the area. No criminal investigation was opened. The first sign that any police were picking up the pattern of murder came in August, 1991, when Detective Sergeant Steve McCann filed a report which connected the death of a gay man, Richard Johnson, 31, (no relation to Scott Johnson) to six other murders or very serious assaults of gay men in the eastern suburbs around that time. Johnson was kicked to death by a group of seven young men on January 24, 1990, outside a toilet block in Alexandria Park, Alexandria. McCann's report eventually formed the basis of Police Operation Taradale, led by Detective Sergeant Steven Page, who would uncover multiple failures in police investigations. But the operation had only been set up after persistent agitations by Kay Warren, whose son, Ross, 25, had gone missing at Marks Park, Tamarama, in 1989. His body was never found. Even though other gay men had died or gone missing at Marks Park, a well-known gay beat, police did not treat their deaths as likely homicides.

Operation Taradale led, in turn, to the senior deputy State Coroner, Jacqueline Milledge, concluding in 2005 that Ross Warren had probably been murdered in a gay-hate crime by being thrown off the cliff at Marks Park. She also rejected the police conclusion of death by misadventure of John Russell, 31, at Marks Park that same year, saying he, too, was probably thrown off the cliff in a hate crime. She concluded that another man who went missing at Marks Park, Gilles Jacques Mattaini, 27, had probably died in ''similar circumstances''. She described the police investigation into Warren's disappearance as ''grossly inadequate and shameful''. She said the police investigation into Russell's death had been ''inadequate and naive''. In June last year, as a result of submissions made by Daniel Glick and Steve Johnson, the Deputy State Coroner, Carmel Forbes, handed down an open finding into Scott Johnson's death. She concluded he could have died as a result of a hate crime. Two weeks ago, on February 11, ABC's Australian Story devoted a program to Johnson's death. The next day, the NSW Police announced a $100,000 reward for information and the creation of Strike Force Macnamir to investigate the death. That still leaves all the people who didn't have the money to hire an investigator, and the multiple evidence trails that have gone cold during years of official denial. Twitter: @Paul_Sheehan_