ROB Knox's murderer Karl Bishop had a history of violence and anger from childhood.

Bishop, now 22, needed to see a psychologist for anger management after he was expelled from Red Hill Primary School in Red Hill, Chislehurst.

During his trial, Bishop revealed he had not seen his father for 16 years and was brought up by his mother along with younger brother Grant.

He studied mechanics at Bromley College, London Road, Bromley, before leaving full-time education at 15.

But by then he was already getting into trouble with police and had convictions for criminal damage and theft.

Bishop, described in court as a "habitual knife carrier", was accused of pulling a butterfly knife on James O'Doherty near a Chislehurst bus stop on July 17, 2003.

It was claimed he said to the victim: "Go on, hit me now and you'll get stabbed up."

That charge was dropped on March 22, 2004, but on December 4 that year he stabbed Mr O'Doherty and Ian Sutherland in East Street, Bromley.

The men said they had intervened after seeing a woman harassed by Bishop and two friends.

Bishop pleaded guilty to wounding with intent and assault causing actual bodily harm at Croydon Crown Court in May 2005.

Bishop, who told the court he carried a knife "for protection", was released in March 2007 and moved to New Eltham, where he worked for an air conditioning firm.

After being laid off, he worked as a window cleaner but said at the time of Mr Knox's murder he was not working and spent his time smoking cannabis and "drinking to get drunk".

He and his family had only moved to Carlton Road, Sidcup, where his mother worked for nearby Lima Cabs, two weeks before the fatal incident.