Only when police produced a till receipt from a shop he visited on the day of the attack did he begin to remember details of his whereabouts. But in interviews a year later, Mr Stone told police that he could not say what he did later that afternoon - the time of the murders.
"I don't know, I can't remember," he said when challenged by detectives to produce an alibi. "I was badly on drugs and ... it was so long ago."
Maidstone Crown Court heard yesterday how Mr Stone, 38, from Gillingham, Kent, was arrested after an appeal for help in solving the crime on television's Crimewatch programme on the first anniversary of the killings. But over more than 20 hours of questioning, Mr Stone repeatedly denied any involvement.
He is accused of the murder of Dr Russell, 45, and Megan, six, at Chillenden, near Canterbury, on 9 July 1996. He is also accused of the attempted murder of Josie Russell, now 11, who was left for dead.
When arrested and asked by police if he would appear in an identity parade, he agreed saying: "I want to, I'm clean. I want to prove I never done it."
Told that his friend, Lawrence Calder, had described seeing him covered in blood the day after the murders, he said: "I ain't done the Chillenden murders. I never had blood on me and I never went to his place with blood on me." The court heard that Mr Stone had burnt all his clothes and bought new ones in the months after the murders. In transcripts read to the court, he said this was because he had put on weight. "I didn't have no respect for myself, I just wore dirty old things," he said.
Detectives asked him what he knew of the murders and why he remembered that Josie had at first been unable to talk but had later recovered some speech. Mr Stone said the case was unusual as Josie had survived to give evidence. "Normally people either kill people or they don't," he said.
The court heard how while on remand in Canterbury prison he was challenged by other prisoners to kill himself. "They were abusing me out of the window and calling me nonce and child killer," he told police. "One of them said, `If you're innocent, come to the window and protest your innocence'. I came to the window.They said, `Get your sheet, tear it in half,' and they told me to hang myself."
Mr Stone said inmates who had given evidence were trying to "fit him up".
Damien Daley, the prisoner in the next cell, told police that Mr Stone had spoken to him of tying people up with wet towels and how one of the victims had tried to run away. But Mr Stone said: "He's a liar, it's getting ridiculous. The evidence against me is getting stupider and stupider."
The trial resumes on Monday.Reuse content