As lawyers for Trevor Hamilton (25) revealed he has yet to show any remorse, they restricted their challenge to just the whole life tariff imposed on him.

Crown Counsel Terence Mooney QC told the Court of Appeal: "In the pantheon of criminal behaviour, there are some crimes, the circumstances of which are so appalling and horrific, that they are forever seared into the public memory. They remain crimes of great notoriety.

"We respectfully say that the murder of Mrs Attracta Harron and the circumstances giving rise to her death by this particular offender is one of those rare offences which will be forever remembered because of its horror."

Hamilton was someone with a "predilection towards violent sexual offences against women" since he was a teenager, Mr Mooney insisted.

Mrs Harron, a 65-year-old mother of five, vanished in December 2003 as she walked home to Strabane after attending Mass just across the border near Lifford, Co Donegal. Her badly decomposed body was discovered months later buried in a makeshift riverbank grave close to Hamilton's home at Concess Road, Sion Mills.

It had also been anticipated that DNA evidence in the case, previously described as questionable by Hamilton's legal team, would come under scrutiny. But opening his case before Lord Chief Justice Sir Brian Kerr and Lord Justices Campbell and Higgins, defence counsel Jim Gallagher QC confirmed the forensics would not be challenged.

Instead, he focused on the fact Hamilton was aged 21 when Mrs Harron was murdered, with convictions for rape and indecent exposure stretching back six years.

The barrister said: "He has effectively no adult existence outside of the prison apart from a few months when he was 17. The defendant's age should have been at least taken into some extent as a mitigating factor."

With Hamilton in court in cuffs and just yards from the Harron family, it was also conceded that he has still to display any regret.

"When a person denies and contests a case effectively, he has no vehicle by which to express remorse which may exist. But I do accept there's no evidence of that," Mr Gallagher added.

"Malign intent"

However, Mr Mooney insisted trial judge Mr Justice McLaughlin was right to hand down the full life tariff and stressed the victim's vulnerability. "He deliberately selected a single lady, single in the sense she was walking alone, enticed her into his car and very shortly afterwards it must have been apparent to Mrs Harron that she was captured by this man who had a malign intent towards here," the barrister said.

Judgment in the case was reserved, but outside the court Mrs Harron's husband, Michael, said: "I'm relieved that he has now accepted the verdict of the jury."