The crazy life of a mixed-race murderer
Before he succumbed to crime and mental illness, John Barrett was a promising singer who had featured in Smash Hits magazine and appeared in programmes about the achievements of young black people.
At the height of his success, he signed a two-year contract with a hip-hop record label as a singer, composer and keyboard player and, as the "voice of 88", was interviewed on radio by Tony Blackburn.
Born in east London in 1963, the son of a Jamaican boxer and a Northern Irish mother, Barrett had a turbulent childhood.
He was beaten by his father and placed in care at the age of six with his four siblings. By the age of 14, his parents had divorced and he had already turned to crime, receiving a two-year supervision order for theft.
The following year he was expelled from school, but he later went to college in Leicester where he received a City and Guilds certificate in dance and drama.
He appeared to be making a new start, immersing himself in music, winning a series of disco dancing championships and making a name for himself as the next big soul star.
But as his success started to fade, he turned to more serious crime to make money. By the time he was 28, he had been convicted more than 25 times and had received eight custodial sentences.
Those close to him believe his descent into mental illness started after he was released from prison in 1994 for robbing a postmaster of more than £10,000 three years earlier.
Anne Bingham, an ex-girlfriend and mother of one his two sons, said he became short-tempered, violent and paranoid.
But it was only a few years later that he came to the attention of mental health authorities. Police referred him to psychiatrists after he went into a police station claiming he was being followed.
In 2000 he was admitted to Springfield Hospital under the Mental Health Act after his girlfriend alleged that he had tried to break her arm, but he was discharged.
He went on to commit further assaults, including another attack on his girlfriend during which she claimed he threatened to wrap a bar stool across her head and hit her with a glass.
It was not until two years later when Barrett pulled out a knife and stabbed three people at a clinic in St George's Hospital that the seriousness of his mental condition was recognised and he was again ordered to be detained at Springhouse Hospital.
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