A PROLIFIC cannabis user stabbed his best friend to death in a schizophrenic rage after becoming addicted to "super skunk" cannabis.
Michael Harris, 21, had been best friends with Carl James, a father-of-one, since they moved into the same street at the age of eight.
His family said his personality changed when he started smoking cannabis at 14 and he developed schizophrenia after moving on to "skunk", a stronger strain of the drug.
Harris developed violent outbursts, became delusional and admitted to his victim, also 21, that he had desires to kill.
Shortly afterwards, he stabbed Mr James six times in the chest on the doorstep of his home, while his fiance and three-year-old daughter were in the house.
Harris then walked home to his mother's house, confessed to the killing and waited for the police to arrive.
He has now been detained indefinitely under the Mental Health Act after pleading guilty to manslaughter at Bristol Crown Court.
At the hearing, it emerged that Harris, who had originally been charged with murder, had been suffering from schizophrenia.
The court heard that Harris had expressed a desire to kill Mr James and had abused cannabis for a long time.
His defence team described him as someone who was an "accident waiting to happen".
His solicitor, Rob Ross, said mental-health workers had been aware of Harris's problems, but did not intervene.
He claimed that Harris's mother had been crying out for help and said: "She felt for some time that something awful was going to happen - and unfortunately something awful did happen."
Speaking after the hearing, Harris's mother, Julie Morgan, 45, of Swindon, Wiltshire, said her family had begged the authorities for help because they feared he was out of control.
She said: "His mental-health problems started at the same time he started experimenting with cannabis. The year before he stabbed Carl he became very ill. He started smoking more cannabis, but it was the stronger stuff and it caused him to become delusional and very violent.
"In the weeks running up to the incident, we became so scared he would try to kill someone we'd even called the police on a number of occasions, hoping they would be able to locate him.
"How much were we supposed to do to get the help he needed? We begged and pleaded, but our case was just ignored until it was too late."
Harris and Mr James had been friends for 15 years after living four doors away from each other in Swindon.
The dead man's mother, Helen James, 57, a grandmother, said: "He was a nice and pleasant kid, but when he hit his teens he started smoking cannabis and went off the rails - his whole character changed.
"He became agitated, aggressive and would have violent outbursts. But the whole time Carl would still be friends with him."
His behaviour spiralled even further in the year before the killing when he started smoking super-strong skunk nearly every day.
He was so erratic that Carl and his fiancee, Emma Lewis, 23, were forced to ban him from their home in Park South, Swindon, to protect their daughter, Daniella.
At 7pm on 4 March this year, Mr James answered a knock on the door and was stabbed six times by a six-inch blade, injuring his heart, lungs and bowels.
Ms Lewis found him lying in a pool of blood. He was taken to the Great Western Hospital in Swindon, but died three days before his 22nd birthday.
At the court hearing last Friday, Rob Ross, defending, said that mental-health workers had been aware of Harris's problems but did not intervene.
Mr Ross told the court: "Harris is someone who, in simple terms, was an accident waiting to happen."
CHEMICAL THAT AFFECTS SANITY
THE danger from cannabis is believed to be increasing due to wider availability of more potent strains such as "skunk".
Stronger strains contain higher levels of tetrahydocannabinol (THC) - the chemical responsible for a cannabis "buzz".
A recent study from the Institute of Psychiatry in London revealed THC reduces activity in an area of the brain that helps keep people sane.
The inferior frontal cortex acts as a check on irrational thoughts and prevents inappropriate behaviour. Brain scans on volunteers showed THC dampens activity in the region.
This was underlined by psychological tests which revealed signs of temporary psychosis.