A campaigning mum who fought to have the ancient double jeopardy law changed following the brutal murder of her daughter was celebrating an historic victory today.

Ann Ming thought her joy would be tinged with sadness, expecting the Government to rule that the change would not act retrospectively.

But Mrs Ming said she was over the moon after Home Secretary David Blunkett surprisingly announced that the double jeopardy rule would be abolished - and it would act retrospectively.

It now means the killer of her daughter Julie Hogg, former labourer William "Billy" Dunlop, could be jailed for life after he confessed to her brutal murder.

Delighted Mrs Ming from Norton, Teesside, said: "I can't describe how I feel. We have campaigned long and hard to get justice for Julie and this in the best outcome we could have asked for.

"I feared the worst before David Blunkett's announcement, thinking the ruling wouldn't act retrospectively.

"But this is the right decision and hopefully my daughter's killer will get the life sentence he deserves and we can finally be happy that justice has been done.

"Dunlop was only over charged with perjury and that was always a poor substitute for the horrible crime he committed.

"This has been a very emotional day for us all, especially for Julie's son Kevin but we are highly delighted with the outcome."

The announcement about the change in the law came as part of Home Secretary's sweeping reforms to the criminal justice system. For 12 years former hospital theatre nurse Ann, 56, and her retired court worker husband, Charles, 77, have battled for justice.

Billy Dunlop was cleared of the body-under-the-bath murder of pizza delivery girl Julie 11 years ago.

And, because of the double jeopardy rule - which prohibits the retrial of a defendant on the same charges - it looked unlikely labourer Dunlop would over be caught.

He had twice walked free after he brutally butchered 22-year-old Julie Hogg to death.

Then, in a case unprecedented in British legal history, justice finally caught up with him when he pleaded guilty to two charges of perjury at Teesside Crown Court, Middlesbrough, in April, 2000. He was jailed for six years.

Dunlop confessed he had lied on oath during the court hearings in the early 1990s, admitting his guilt to a female prison officer while serving a separate seven-year jail sentence for an unrelated assault.

Dunlop went on trial twice after he was accused of the gruesome killing of young mum Julie, who vanished from her home on November 16, 1989.

Julie, who had a three-year-old son Kevin at the time, disappeared without trace after she was dropped off from work by her boss during the early hours of the morning.

A full scale police hunt was launched and police spent a week inside Julie's home searching for any scraps of evidence which might give a clue to her whereabouts. Still, they could not find her.

Then, three months later when police returned the keys of the property to Julie's mum Ann the grim truth became known.

The pizza girl, who was in the process of divorcing her 27-year-old husband Andrew at the time, had been sexually assaulted, mutilated and her body was stuffed behind the bath panels.

It lay there until it was found by her horrified mum on February 5, 1990. Mrs Ming had been alerted by the overpowering smell coming from the bathroom and she was later to receive a £20,000 compensation payout after suing Cleveland Police over the bungled search.

Dunlop, who lived in the area near Julie's council home in Grange Avenue at Billingham, Teesside, was arrested and charged with her murder.

In May 1991, a jury at Teesside Crown Court failed to reach a verdict and was discharged by the trial judge after a three-week hearing.

At a re-trial in October of the same year Dunlop, then 28, walked free after spending 20 months behind bars on remand.

The jury at Newcastle Crown Court again could not agree a verdict after a nine-day trial. Judge, Mr Justice Ognall, brought in a formal not guilty verdict.

Both juries had been told by the prosecution that Dunlop had murdered Julie in a frenzy after she spurned his advances and refused to have sex with him.

It was alleged he had hidden her body behind the bath panels hoping to return later to dispose of it, and her keys with his fingerprints on were found under floorboards at his lodging house.

Tests were also done on 21 men - six of whom admitted having had sex with Julie - who knew the victim.

Only Dunlop had the same DNA profile as was found in semen traces on the blanket in which the victim's body was wrapped.

Dunlop, formerly of Floddon Way, Billingham, denied the murder. He claimed he had been framed and during the re-trial he said he had not smothered Julie.