A builder who raped and brutally murdered a teenager in her South Hampstead home has been told he is likely to die in prison after evading justice for “half a lifetime”.

Ham & High: Murderer James WarnockMurderer James Warnock (Image: Archant)

James Warnock, 56, was given life with a 25-year minimum term at the Old Bailey this morning for the 1982 murder of Yiannoulla Yianni, 17, after the judge said he had inflicted “misery beyond measure” on her family.

He was also sentenced to 20 years for raping the schoolgirl and given another five years and one month for six separate counts of possessing and distributing indecent images of children, to run concurrently.

Members of the Yianni family shed tears whilst Warnock remained impassive in the dock as Judge Nicholas Hilliard handed down the sentence, telling him: “Yiannoulla’s family do not even have the small comfort of knowing that her death was swift. It was not.”

The judge said he was satisfied there was a degree of “premeditation and planning” before the murder, and that it was not “a spur of the moment” crime.

Ham & High: The Belsize Road house where Yiannoulla Yianni was murderedThe Belsize Road house where Yiannoulla Yianni was murdered (Image: Archant)

He said he believed Warnock, who was 22 and married at the time of the murder, had spotted the teenager either at her father’s shoe repair shop, or in the street, and had made advances to her, which she had “politely rejected”.

On August 13 1982, he went to her home in Belsize Road, close to his Adelaide Road home, and knocked on the door when she was preparing dinner for her family – “a dutiful daughter to the last”, in the judge’s words.

After Yiannoulla again spurned him on the doorstep, Warnock forced his way into the maisonette, where he subjected the teenager to a terrifying ordeal before strangling her to death.

He chased her around the house, first into her brother’s bedroom and then into her parents’ room, where he raped and killed her.

At some point, he also ran the bath – perhaps in an attempt to drown his victim – and used a knife to cut open her clothes and possibly to force her into the bedroom.

Her parents found their daughter lying on their bed, in a scene described as being “like something from your worst nightmares”.

She was naked from the waist down, her body covered in bite marks and other injuries, and her mother realised she was dead because “her head had dropped”.

The judge told Warnock: “This was a sustained attack in which you terrorised her for some time…You strangled her to death to avoid identification”.

Taking Warnock’s age and the law as it stood in 1982 into consideration, the judge said he must serve at least 25 years behind bars – meaning he will be 81 before he can be considered for parole.

Judge Hilliard praised the role of local press in helping to keep the case in the public eye over the years when initial national interest in the case faded after several failed appeals to help catch the killer.

He said: “Publications such as the Camden New Journal and the Hampstead and Highgate Express are great examples of papers working for their local communities.”

He also paid tribute to Yiannoulla’s father, George, who he said “worked tirelessly to keep the case alive” before his death from a brain tumour in 1988.

Yiannoulla’s sister and two brothers were in court, along with former school friends and detectives who worked on the case at the time.

Her sister Maria said afterwards: “We are just trying to take it all in at the moment, but yes, we are feeling satisfied. The sentence was never going to be enough because it can never bring her back, but we feel that at last, justice has been done.”

Warnock was finally snared last year when police obtained his DNA after he was arrested for the child pornography offences, and matched it with semen samples taken from the Yianni family home.

He denied the murder and concocted a story that he had been in a consensual sexual relationship with the teenager to explain why his DNA and fingerprints were found at the house.

But the jury did not believe his lies after the prosecution exposed multiple inconsistencies in his account, and found him guilty of rape and murder after just two hours of deliberation on Friday.

This morning, the judge told Warnock that Yiannoulla was an innocent virgin when he attacked her, and that her memory as a loving, sweet-natured, lively and kind daughter lives on.

He said: “Such was the brightness of her spirit that she still refuses to be defined by the awful things you did to her.

“Instead, she remains captured for all time by the photo we have seen of the happy and hopeful 17-year-old.”

When arrested and questioned by police over the teenager’s murder, Warnock denied knowing she had been killed – in spite of a huge public appeal at the time – claiming he generally only read the sports pages of newspapers.

The judge said today he believed Warnock had spent the past 34 years “picking up such details as you could about Yiannoulla in case the connection to you should ever be made.”

Of the long wait for justice for Yiannoulla, he said: “It is often said that the file in the case of murder is never closed and that is certainly true here.”

Detective Inspector Julie Willats, from the Homicide and Major Crime Command, said following the conviction: “After 34 years I am so pleased that today we have seen Yiannoulla’s killer brought to justice. I hope this will bring peace for her family who have lived through decades of grief. Today is testament to the unrelenting, dedicated work of scientists and detectives who over many years never gave up hope of catching the killer, and also to the local community that supported them.

“Yiannoulla was a vibrant young woman with her whole life ahead of her, a bright future planned and supported by her loving family. To have finally tracked down and convicted her killer after all these years is immensely satisfying.

“I’m sure Warnock thought he’d never be caught but historic murders such as this are never ‘case closed’. As we have seen, advances in DNA technology can play a huge part in solving older cases and, no matter how long it takes, the Met will always strive to bring offenders before the courts.”

Yiannoulla’s family, who knew her as Lucy, said following the verdict: “For over half a lifetime we have had to live with the daily torture of what happened to our daughter and sister Lucy.

“All who knew her, loved and adored her. Even through her death she deeply touched those involved in the investigation of her murder. We thank, from the bottom of our hearts, the police both past and present who have worked constantly and tirelessly to bring him to justice, especially those over the last six months. Our love and thanks to all who gave evidence and helped in this trial and to the family and friends who have supported us throughout.

“We now pray that we can move forward with the rest of our lives having some peace in knowing that her killer has been brought to justice and that a very dangerous man is no longer a threat to anyone else.”

Additional reporting by Maria Geftar