Gordon Hamilton did not live long enough to be held to account for his part in the murders of Helen Scott and Christine Eadie. He died a grubby, anonymous death 10 years ago. Of four people at the World's End on the night of October 15, 1977, only Angus Sinclair remains alive.

Sinclair said at the outset of his trial that Hamilton murdered the girls. After the collapse of the trial, no-one will ever really know what happened that night, but DCI Allan Jones, the senior investigating officer, said: "As far as we are concerned, Hamilton was not the instigator."

Hamilton was 15 when he first met Sinclair, the age at which Sinclair himself began offending. He lived on Stirling Road in Townhead - near where Anna Kenny vanished in 1977 - with his parents.

Sarah, Sinclair's estranged wife, still feels fondly for her brother. She accepts his involvement in the murders, but lays the blame on her husband. Nevertheless, she believes it was her brother who first struck up a conversation with the two girls.

"Angus could never have got those girls on his own," she said. "Only Gordon could have. Gordon was a handsome, lovely-looking man. I had no idea Gordon was involved, but he never murdered either of those girls. He was an accomplice but was manipulated by this creature Angus Sinclair. I know in my heart he corrupted Gordon. It wrecked Gordon's life."

DNA evidence proves Hamilton had sex with Helen Scott and Christine Eadie. Whether or not he played a direct part in their murders is not known, although detectives do not believe he was involved in any of the other unsolved murders from the same period.

Hamilton had a huge row with Sinclair in 1978 and they never spoke again. In a twist so coincidental it seems improbable, a year after the World's End murders Hamilton met a woman called Wilma Sutherland in the Hurdy Gurdy bar. They married shortly afterwards.

Wilma Sutherland was the last person to see Anna Kenny alive in the same bar the previous year. Sinclair is the chief suspect in Anna Kenny's murder. Detectives were amazed at the coincidence, as was Sarah Sinclair. She said: "I don't think Gordon was involved in that, but I think there's too much of a coincidence to say that there was nothing there."

Hamilton had a job in a button factory in Glasgow, where he worked until 1982. By the time he was in his late thirties, Hamilton had split from Wilma and was an alcoholic, drifting in and out of homeless hostels in Glasgow. Former girlfriends said he could be violent, but police said there was no evidence that he was "overtly sexualised".

In 1994 he was living in Robertson House, a hostel in run-down Mile End, in the east of the city. Many of the residents were convicted paedophiles and rapists; almost all were drug addicts or alcoholics.

In 1997, he died of a heart attack at the Royal Infirmary. He was 41.