The jury heard a great deal about Michael Chudley’s state of health, both physical and mental.

Chudley suffered a heart attack in 2009 while working on the project to build an extension to Mr Sear’s house in Esher, Surrey. The court heard that Chudley is currently on a wide range of drugs for angina, high blood pressure, high cholesterol, water retention and other conditions.

But it is his mental health that formed the basis for the defence case that Chudley was not guilty of murder but guilty of manslaughter on the grounds of diminished responsibility.

Consultant forensic psychiatrists Dr Andrew Johns, who was called by Chudley’s defence team, and Dr John Sandford, called by the Crown, agreed that Chudley’s claims of having amnesia in the days before he shot Mr Ward in his office with a sawn-off shotgun were not credible.

They also agreed that Chudley suffers from a paranoid personality disorder, which led him to harbour hatred for Mr Ward and blame him for becoming bankrupt, homeless and alone.

But Dr Johns told the court that he believes that Chudley’s condition represents an abnormality of mental function that means he would not have been responsible for his actions on the day.

He told Ian Glen QC, defending: “Mr Chudley’s condition, in my experience, is unique and it is more likely than not that his personality disorder played a part in what happened.”

But he added: “I have no doubt Mr Chudley is a dangerous man. I am concerned he is so fixated on wrongs he believes were perpetrated on him by Mr Ward. It is the persistence of those ideas that mean he is a risk to other people.”

But Dr Sandford said that he did not believe that Chudley’s obsession with Mr Ward was evidence of an abnormality of mental function within the meaning of the law that would support a verdict of manslaughter by way of diminished responsibility.

Dr Sandford said: “The issue is did he have the ability to act rationally. I believe he did and said I’m not going to act rationally. I can’t find any psychiatric evidence of any abnormality of mental function.”