Marc Traylor was psychotic and “more likely than not” insane when he stabbed his daughter, a top consultant forensic psychologist has told a jury.

The 42-year-old father-of-three was shot by police after he held the teenager a hostage at their home in The Avenue, Hersden.

A jury at Canterbury Crown Court heard that Traylor was diagnosed as suffering from paranoid schizophrenia in 2012.

Twice he was admitted to mental hospitals after believing his wife was having an affair and that he was being poisoned.

Traylor suffered from delusions and was convinced people were trying to kill him, Dr Ian Cumming told the court.

Traylor also claimed his wife had been on X Factor in 2002 and had teamed up with an American girl.

The psychiatrist said: “These were very bizarre, in fact, very mad beliefs.”

He told the jury that on another occasion Traylor booked into an hotel and was discovered on the roof after claiming he could hear voices of people who were threatening to kill him.

Traylor later grabbed a nurse around the neck and punched her and it had taken six members of staff to restrain him before he was moved to a more secure unit.

Dr Cumming added that Traylor was later allowed to return home after making a recovery and given anti-psychotic medicines under a Community Treatment Order.

But Traylor’s family believe that weeks before the incident in February 2015 he had stopped taking the drugs and signs the illness was returning were spotted by his family.

Defence barrister Tyrone Smith QC said the evidence had shown that Kitanna, who was held hostage, had been Traylor’s “favoured” daughter.

He had told her he loved her “more than his mother” and had confided to his father he had wanted to "protect" her.

Dr Cumming said Traylor “was probably terrified that something was going to happen and was driven by those beliefs”.

He added: “It was clear that he had lost contact with reality. It is very clear he had no sense of what was going on, no sense of the danger he was in and no idea of what was right or wrong.”

He was asked if it was possible to know if Traylor – who has no memory of the incident – would have had any idea of his actions at the time.

He replied: “It is just not possible to make sense because it is all very illogical... all very psychotic. In my opinion, he would have had no thoughts that his actions were wrong.”

Earlier, the jury heard from one of the firearms officers called to deal with the siege, known as Officer L.

He said that as officers were trying to reason with Traylor, who had armed himself with two knives, they asked if he needed anything.

Traylor replied: “Yes, two more knives!”

As Officer L was next to the bedroom where Traylor and Kitanna were, he saw one of the negotiating officers, called Officer G, “flinch”.

He said the officer raised his taser and fired it and then heard someone say: “Get in”.

“There was a lot going on and I got myself across the barricade. There was a girl there who said: ‘I’ve been stabbed’," he added.

He said he then fired a taser but it missed and he saw Traylor, with a hand around Kitanna, on the floor kicking “wildly”.

The officers said the teenager was screaming and Traylor was stabbing her “between three and four times.” and his face “was a mixture of determination and anger”.

Officer L said he fired his 9mm pistol at Traylor’s stomach to stop him – but the stabbing continued.

“I thought she was being killed. This was a frenzied attack, “ he added.

He told a hushed court he had then fired two more shots at Traylor’s head intending to kill him and bring an end to the stabbing.”

Traylor’s barrister told the officer: “If you hadn’t done that, there was a real risk that a young lady would have died and I am not criticising you for your actions on that day.

“There are a number of people in this court who are grateful for what you did that evening.”

The jury is being asked by both prosecution and defence to bring in a special verdict that Traylor was not guilty of trying to murder his daughter on the grounds of insanity.