Sgt Matiu Ratana: Accused was thinking clearly when gun fired, jury told

A man accused of murdering Metropolitan Police custody sergeant Matiu Ratana was "thinking very clearly" before he fired the gun, a jury has heard.

A consultant forensic psychiatrist told Northampton Crown Court Louis De Zoysa showed "a clear ability to control his actions" before he shot Sgt Ratana.

Dr Nigel Blackwood added he did not believe the 25-year-old had a defence of diminished responsibility.

Mr De Zoysa denies murder, telling the court he had not meant to fire the gun.

The prosecution argues the defendant, from Banstead in Surrey, "pulled the trigger on purpose four times" while he was handcuffed in a holding room at Croydon custody centre on 25 September 2020.

Appearing as an expert witness for the Crown, Dr Blackwood told the court he did not believe Mr De Zoysa was hyperventilating during footage showing him inside a police van.

"He takes a physically deep breath on a couple of occasions. He clearly requests an appropriate adult, mentioning his vulnerability, and he asks for the duty solicitor," he said.

"This is clearly somebody that is thinking ahead to the police station."

Dr Blackwood continued: "He is not in a hyper-aroused state unable to think clearly, he is thinking very clearly and logically in that moment.

"He answers police questions appropriately - there is nothing in that series of interactions (with police officers) that, because of his autism, he is struggling to understand."

The consultant forensic psychiatrist went on to tell the court he had interviewed Mr De Zoysa on four occasions and found him to be highly intelligent.

He said he did not think there was any relationship between the defendant's autism and his decision not to tell officers he was carrying a hidden gun.

Prosecutor Duncan Penny KC also asked the expert witness for his view of defence suggestions that Mr De Zoysa's use of the gun was "uncontrolled and impulsive".

Dr Blackwood answered: "I don't think that emerges from the evidence that we have.

"He demonstrated a clear ability to control his actions. He retrieves the gun, has it in his hand, has time to consider what he is going to do with it, and then discharges it."

During cross-examination, Imran Khan KC asked Dr Blackwood about a comment made by Mr De Zoysa about a "need for personal space", which the defence claims shows the "trigger" for the alleged meltdown.

Mr Khan asked Dr Blackwood if it had surprised him an autistic meltdown had been suggested by a separate consultant forensic psychiatrist, called on by the defence.

Dr Blackwood responded: "When you look at all the evidence in the round, yes it did."

The trial continues.

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