Dental experts linked a bite mark inflicted one hour before she died to the last person she was seen alive with. The beautiful young drama student had been brutally attacked then strangled.
But Francis Auld was able to walk free from court. A jury found the charges against him not proven – a verdict unique to Scotland - that allows an accused to be acquitted of the crime in exactly the same way as a not guilty verdict.
The verdict shocked the country. On the night of her death, Amanda Duffy had been celebrating with pals in her home town of Hamilton after an audition at the Royal Scottish Academy of Music and Drama in Glasgow.
As they walked to a taxi rank, Amanda was approached by Auld and her friends left the two talking. Later that night, 30th May 1992, her body was found by passers-by on deserted waste ground.

Auld, who died in 2017, claimed he had left Amanda after being chased off by a mystery man called Mark, who he insisted was her killer. The man was never traced.
In a joint minute of admission accepted by crown and the defence that he had savagely bitten her breast yet maintained that someone else had subsequently come along shortly afterwards and murdered her.
This paragraph is key: “An injury to the right breast was caused by a human bite. This would have bled and was inflicted within an hour prior to death. It would have been “excruciatingly painful”, and was an active, aggressive bite, rather than a “love bite”.
‘The dental features of the bite corresponded with those of the respondent, leading to the opinion that he had caused the bite. That he had done so was agreed by joint minute.
On 5 June 1992, medical examination of the respondent revealed injuries on his arms, left hand and neck consistent with having been caused by fingernails.”
But a jury allowed him to walk free. Cops at the time called it a “perverse jury” who had gone against the evidence. They were terrified of sending an innocent man to prison.
In 1995, Amanda’s parents Joe and Kate, raised a private civil action against Auld. A judge found him responsible for her death
The legal implications of the not proven verdict are the same as not guilty. Acquitted and innocent in the eyes of the law.
Supporters of the verdict say it offers additional protection for the accused but it’s a bitter pill to swallow for all parties. Where’s the closure for families when there is no-one else in the frame for the crime? And what of the accused? Neither innocent nor guilty - and it’s a cloud that will hang over them until the day they die or new evidence surfaces.
Scotland’s three verdict system is outdated and devastating for families. It doesn’t give any answers and it allows those where the evidence points to guilt a get out of jail free card.
Today in this paper the family of a man who was murdered and watched the cabbie accused walk free from court say the verdict was a shock they didn’t even consider. Craig Kearney, 24, was found bleeding to death in an East Kilbride road in March 2017 after a row with taxi driver Derek McClinton - who was accused of deliberately running him over.
McClinton admitted “clipping” the amateur footballer with his cab and driving off during his trial at the High Court in Glasgow earlier this year.
But Craig’s mum and dad, Barry and Marie couldn’t believe it when the jury returned their verdict. “You’re not guilty but if you are then don’t do it again” it screams. A moral judgement that hangs over the heads of everyone involved.
You’re either guilty or you’re not. There can be no half measures. It’s an insult to the victims and an insult to anyone who really is innocent of the crime for which they have been accused. A dated law has no place in a modern justice system. Even in a country that prides itself on being distinctive.