A jury trying the case of a man who stabbed his neighbour to death was given the task of deciding whether his diagnosed personality disorder gave him a defence to murder.
Can Arslan, 52, killed Matthew Boorman on the victim’s front lawn in Walton Cardiff, near Tewkesbury, Gloucestershire, on October 5 last year.
He also knifed the victim’s wife Sarah in the leg before forcing his way into the home of Peter Marsden and stabbing him eight times.
Arslan, who has a paranoid, unstable and antisocial personality disorder, had been threatening to kill Mr Boorman and other neighbours for years.
In the wake of the attacks, he feigned symptoms of psychosis, including hearing voices telling him to kill, and amnesia of the event, and also claimed to be suicidal.
Two forensic psychiatrists agreed Arslan was not mentally ill but were divided on whether his personality disorder should lessen the offence to one of manslaughter on the grounds of diminished responsibility.
Arslan’s condition manifested itself in extreme anger and aggression to perceived slights and an overinflated sense of his own importance, the jury at Bristol Crown Court was told.
The defendant had a tendency to believe others were jealous of him and make “grandiose” claims about his exploits.
Dr John Sandford said CCTV footage of the attacks makes it clear that Arslan was aware of what he is doing in the present moment.
He said Arslan was able to understand and respond to people screaming at him, telling one neighbour: “You’re next.”
When confronted by police brandishing a Taser, the defendant dropped the knife and got to his knees.
“It’s quite clear he knows what’s going on and why he’s been arrested,” Dr Sandford said.
The doctor noted that, although he was not mentally ill, Arslan would routinely make narcissistic and false claims about himself.
“What I mean by that is that he just makes up things to make himself look good – claims about having money, having rich relatives, having gangsters in the family,” Dr Sandford said.
“His self image was of a proud and a hard man, a very tough man who had done military service.”
The witness added: “(Arslan) is an angry man who in quite a controlled way is acting out his rage by taking someone else’s life.”
But Dr Sally Foster, who conducted a psychiatric examination for the defence, said Arslan’s personality disorder diagnosis might provide a defence to murder.
She found that, although the defendant appeared to be rational during the attacks, the decision to go out and kill was not rational.
Dr Foster found “impaired mental functioning was a significant contributing factor to the defendant’s acts”.
She said he was more likely than others to lose control in circumstances where he feels threatened.
Dr Foster said Arslan’s personality disorder amounted to an abnormality of mental function, but said it was for the jury to decide whether that was sufficient to lessen the offence from murder to manslaughter.
Arslan was found guilty of murder by the jury on Tuesday and will be sentenced later.
