A 44-year-old builder described as a "dangerous smooth operator" was today found guilty of abducting and murdering his 15-year-old niece Danielle Jones.
A jury at Chelmsford crown court took more than seven hours to convict Stuart Campbell, of Grays, Essex, of killing Danielle following an 11-week trial.
After the verdict, it emerged that Campbell has a lengthy criminal record and had been given a prison sentence for holding a 14-year-old girl without authority in 1989.
Passing sentence, the judge, Mr Justice McKinnon told Campbell: "You have been a blatantly deceitful and thoroughly dishonest smooth operator over many years." He added: "You have done a truly terrible thing that has caused widespread horror and disgust. It seems to me you are a dangerous man."
Campbell, who was dressed in a sombre blue suit, showed no emotion as the verdict was returned. He calmly picked up a file before being led out of the dock to begin his sentence.
Danielle's parents Tony and Linda Jones hugged each other in the public gallery as the jury of seven women and five men returned the guilty verdicts.
Campbell had denied abducting and murdering Danielle, who vanished on June 18 2001 after leaving her home in East Tilbury, Essex, to walk to a nearby school bus stop.
But routine checks showed that the teenager's uncle, who lived with his wife Debbie nearby, had a history of violence and had been obsessed with teenage girls throughout his adult life.
Campbell, a builder and bodybuilder who will be 45 in February, has a criminal record dating back to his early teens, when he was convicted of robbing a 12-year-old girl.
His record includes a suspended prison sentence for holding a 14-year-old girl without authority and a four-year sentence for robbery. Several women have also come forward to tell police how they had been abused by Campbell when they were teenagers.
Officers discovered that Campbell made several approaches to young girls in the street. He pretended to be a professional photographer or a representative from a modelling agency and tricked girls into posing in various states of undress at his home. He also photographed girls as they walked past his home.
Campbell was obsessed with internet pornography, downloading indecent images of girls from websites with names such as Young Lolita Beauties.
He and Debbie - who is in her 30s, and works for a London insurance company and was pregnant with their only child when Campbell was arrested - began seeing each other when he was in his 20s and she was about 15.
When officers learned that Campbell had been fixated with Danielle, they became certain that they were on the right track. Police discovered that Campbell had kept a diary detailing his contacts with Danielle, sent her text messages - some of which Danielle returned - and left handwritten notes in her bedroom.
They also believe that he stole films from a drawer at Danielle's house taken on her 15th birthday party and on Millennium Eve.
Campbell called Danielle "Princess" - the same term of endearment he had used for Debbie when they began seeing each other.
Detectives became certain that Campbell was having an inappropriate relationship with Danielle. They suspected that the relationship was sexual and illegal, and that Danielle had been trying to extricate herself from the relationship.
Police believed circumstantial evidence was compelling
Although Danielle's body was never found, and much of the evidence linking Campbell to the case is circumstantial, police believe it is compelling.
A witness saw Danielle talking to "a man in a blue van" shortly before she disappeared - a van which matched Campbell's work van. Police found a green canvas bag in Campbell's loft containing women's underwear and a pair of white cling-top stockings. On the stockings they found blood; forensic tests later showed that the blood contained a mixture of Danielle's and Campbell's DNA.
Mobile phone records revealed that Campbell's phone and Danielle's were almost certainly together in the hours after Danielle vanished.
It also showed that Campbell was not, as he claimed, buying bolts at a builders' merchant in Rayleigh, Essex, when Danielle was last seen.
Friends and family bombarded Danielle with text messages after she disappeared. Danielle replied to none of them. Only two messages were sent from her phone after she vanished - both to Campbell's phone. The first said she was in trouble at home. The second thanked Campbell for "everything".
A linguistics professor noted that the two messages contained small but significant differences when compared to Danielle's normal texting style. For example, Danielle normally spelled the word "what" as "wat" when texting. But after she vanished the spelling changed to "wot".
Detectives are certain that Campbell sent the messages to himself from the teenager's phone and made tiny but telling errors when trying to ape her texting style.
