Callum Wheeler was described as “a complete and utter loner” who spied on police as they investigated the death of the woman he had killed.
The 22-year-old had no known friends, few numbers stored in his mobile phone and would spend most of his time alone in his bedroom.
In his trial, the jury heard that he accessed a number of pornography websites in the days before and after Julia James’ death and looked up rape.
He was so isolated that he barely knew his own brother, police said.
Wheeler, his father and one brother had moved to the Kent village of Aylesham from London two years before Mrs James died, after Wheeler’s parents separated and his mother stayed in the capital. He also had another brother.
He was known to go and watch football at the local sports centre on Tuesdays and Wednesdays, and played computer games, but had no job and was not studying at the time of Mrs James’s death.
Police said that he had left school around the age of 15 and had no formal qualifications.
Senior investigating officer Detective Superintendent Gavin Moss said: “I would describe him as a complete and utter loner. Normally in our investigations we get into the absolute detail of people, and we find out how they live their life.
“He spent most of his time watching TV in his bedroom. He had no friends, normally we’re able to explore about associates. His mobile telephone had very few contacts on it.”
Investigators also believe from sightings around the area that Wheeler was watching as officers scoured the area for clues, following the death of one of their colleagues at his hands.
Mrs James was beaten to death as she walked her dog near Ackholt Wood in Kent.
The investigation was one of the biggest undertaken by Kent Police in recent years, with 1,100 officers and staff involved in the painstaking inquiry.
Mr Moss said that a few days after the killing in nearby Spinney Lane “a witness saw a person she described as Callum Wheeler looking down towards the direction where the officers were working, watching”.
He believes Wheeler had been doing the same thing when he was photographed the day after Mrs James died on April 28, still carrying the weapon in his blue holdall.
Investigators are still no clearer as to why Wheeler packed the railway jack in his bag, walked around the Kent countryside and killed an innocent woman.
There was no known connection to his victim and Wheeler told police he did not know her, and he had no history of violence.
During the trial, jurors heard that Wheeler said Mrs James was a “copper” who “deserved to die” while he was remanded in custody at Maidstone police station.
He also tried to pull down his trousers to masturbate while in a cell, prosecutors said.
During his trial for murder at Canterbury Crown Court he behaved erratically in the dock, at times sitting hunched over or staring blankly into space.
He was warned by judge Mrs Justice Cheema-Grubb not to talk as the prosecution began opening their case, and in the final stages of the trial had to be carried in to the dock.
The jury heard there were no signs of a “sustained or violent” sexual attack on Mrs James, according to the pathologist who carried out a post-mortem examination, though it was not completely ruled out.
Nothing was taken from Mrs James – only her house key has never been found.
Enjoy the convenience of having The Sunday Post delivered as a digital ePaper straight to your smartphone, tablet or computer.
Subscribe for only £5.49 a month and enjoy all the benefits of the printed paper as a digital replica.Subscribe