A former soldier accused of murder carried a knife because the medical condition he suffered from made him fearful, a jury has been told.

Brian Rudwick, 34, of Tarner Road, Brighton, has denied murdering his wife's ex-husband Bill Davey at a trial at Lewes Crown Court.

Mr Davey, 41, a father-of-six, was stabbed six times with a combat knife and had his throat cut outside his home in Nuthurst Place, Whitehawk, Brighton, on February 15.

The court has heard there was ill-feeling between the two men and Rudwick had been carrying a knife whenever he went out for three months before the killing.

Rudwick, a former jailer at Brighton Magistrates Court, has told the jury he accepts he killed Mr Davey but says he has no memory of the incident.

He has been diagnosed as suffering from post-traumatic stress disorder caused by his abusive childhood and incidents he witnessed while serving in Northern Ireland. He suffers from disassociation disorder, which causes him to have temporary memory loss.

Professor Nigel Eastman, a consultant forensic psychiatrist, told the jury: "It is not for a doctor to comment on why he went out with a knife.

"But what I can say is carrying a knife is medically understandable in this man because he was very fearful and part of the basis of his fear was his medical condition."

Professor Eastman said Rudwick's personality had been shaped by the physical abuse he suffered as a child.

He said: "This is a man who has developmental post traumatic stress disorder because he was traumatised as a child repeatedly so his personality has been shaped by that."

Professor Eastman said it was believable that Rudwick could not remember details of the stabbing because he had previous episodes of memory loss over a number of years.

The trial continues.