IT has been a long, arduous journey, fuelled by a steely determination and a mother's love for her child.

On Monday, Ann Ming will finally see her 15-year battle to change the double jeopardy law come to fruition after a tireless crusade, supported by The Northern Echo and its readers, MPs, Lords, victims' families, friends and charities.

When she embarked on her campaign, Mrs Ming vowed not to give up until the killer of her daughter, Julie Hogg, was behind bars.

Billy Dunlop, a labourer from Billingham, near Stockton, was acquitted of Julie's murder after two juries failed to reach a verdict. He later admitted killing her.

Under the double jeopardy law, he could only be convicted of perjury for lying under oath at the original trial.

He was jailed in May 1998 for assaulting a former girlfriend and received an extra six years on his sentence in April 2000 for perjury.

Mrs Ming hopes he could face a retrial under the legislation, which is retrospective.

But there is still a long way to go.

The Director of Public Prosecutions must first approve Cleveland Police's re-examination of the case and any application to the Court of Appeal for a retrial.

From there, the Court of Appeal must be satisfied that there is new and compelling evidence against Dunlop and that it is in the interests of justice to bring him to court.

Julie, a pizza delivery girl, was 22 when she disappeared from her Billingham home, on November 16, 1989.

Cleveland Police carried out a fingertip search of her house, but found no clues, and Julie was put down as yet another missing from home.

It was only when officers returned Julie's keys, three months later, that Mrs Ming discovered her daughter's body behind the bath panel.

Labourer Dunlop was charged with murder. Despite forensic evidence, he denied the charges and claimed he had been framed.

Two juries were unable to make up their minds, and after the second trial, he was formally acquitted of the crime. Afterwards, he protested that police should "find the real killer".

Dunlop even consulted a lawyer with a view to getting compensation for the 20 months he spent in jail waiting for the trial. And he added: "The police have been pointing the finger at me for 20 months. I'm just relieved it's all over."

That may have been the end of the affair if it was not for his confession to a prison officer in 1999. The result of his unburdening meant Dunlop was given a six-year jail term for perjury.

He confessed to lying under oath during the murder trials but could not be retried for the murder because of the 13th Century "double jeopardy" law.

The 800-year-old ruling states that anyone cleared of a crime cannot be tried twice for the same offence, even if they later confess or if police discover new evidence.

The rule was meant to protect the public against malicious and vindictive prospecution but, sometimes, it protected the guilty at the expense of the innocent.

The possibility of reforming the law had already been mooted when Dunlop made his confession.

It was one of the key findings contained in The MacPherson Report carried out into the circumstances surrounding the death of Stephen Lawrence.

To those in favour of it, the double jeopardy rule was an important democratic safeguard against autocratic governments.

They claimed that if police know they can always go back there is no incentive to them to get the evidence right in the first instance.

It's a principle that had existed for 800 years and had been adopted by legal systems across the world - so why change it?

But the blatant miscarriage of justice surrounding Julie Hogg's murder added support to calls for reform which led directly to the Government's decision to scrap the rule in exceptional cases.

As former policeman Lord MacKenzie of Framwellgate said: "If the law is going to be held in high regard by the public it must be even handed.

"Provided there are proper safeguards, a miscarriage must be capable of being put right whether it be a wrongful conviction or wrongful acquittal."