A firearms officer cleared of murdering Chris Kaba should never have been put on trial, a former colleague of his has told the BBC.

Metropolitan Police officer Martyn Blake, 40, fatally shot Mr Kaba – who was not carrying a gun – during a vehicle stop in Kirkstall Gardens, Streatham, in September 2022.

The unnamed colleague, who was at the scene immediately after the shots were fired, said: “At no point was there any evidence that Martyn Blake had done anything wrong or at least deviated from his training or indeed the law.”

The Crown Prosecution Service has defended its decision to bring Mr Blake to trial.

It said the decision to prosecute had been made “after an in-depth consideration of all the available evidence”.

About 150 people gathered for a vigil outside the Old Bailey on Monday after jurors returned their verdict.

Mr Kaba’s cousin Sheeda Queen said the family was “devastated” by the outcome.

“The acquittal of Martyn Blake isn’t just a failure for our family but for all those affected by police violence,” she said. “Despite the verdict, we won’t be silenced.”

Mr Blake’s former colleague, who asked not to be named and has since left the force, told the BBC’s Today programme that he believed a system similar to Army court martials would be more appropriate for cases such as this.

“Martyn is the most professional, assiduous, diligent police officer you will come across and he should never have been put in this position,” he said.

“He was on Kirkstall Gardens that night on behalf of the state. The state put Martyn Blake there that night and the state trained him to do the fearsome thing that he had to do and he should never have been named in the media.”

The former officer, who was part of Met’s MO19 specialist firearms command, said he had administered first aid at the scene and been involved in procedures that followed the shooting.

Mr Kaba, 24, had been followed and stopped by police because the car he was driving had been linked to a previous shooting in Brixton.

After being boxed in by police cars, he drove his vehicle backwards and forwards as he tried to ram his way free.

Mr Blake told the trial that he had believed one of his colleagues would be killed and he opened fire to stop the car.

Mr Kaba died from a single gunshot wound to the forehead.

Mr Blake’s colleague said police officers were not above the law but incidents like these should not be dealt with in criminal courts, where juries had the power to clear or convict defendants.

He said: “I think it’s important they are viewed as fully accountable to the law and in front of the public. However, there is a problem when police officers are scrutinised by people who don’t necessarily understand the pressures and the issues involved.

“I do wonder if there is something more akin to the court martial system that we see in the military that would be a better fit for incidents like this, where we have a panel of legal experts, a panel of subject matter experts that we can call on.”

He said that while Mr Kaba had been found not to have had a gun, describing him as having been unarmed was “problematic”.

“It implies that Mr Kaba was presenting no threat to the officers who were dealing with the incident on that night and obviously the court heard something very different,” he said.

“The case of the defence was essentially that Mr Kaba was armed with a 2.5 tonne high-powered Audi which could absolutely have presented a lethal threat to the officers involved.”

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Describing the jury’s verdict as the “right decision”, he said: “There was no visible or audible glee by anyone I saw in the courtroom, anyone connected to policing or connected to Martyn.

“There was just an acceptance that the right thing had happened and the right outcome had been achieved. There are no winners in this situation and there were no winners in the courtroom yesterday.”

Justice Secretary Shabana Mahmood told BBC Breakfast that the “due process of the law” had taken place and this should be “respected”.

But she acknowledged the trial had thrown up issues of trust both in black communities and within the police.

“The job that firearms officers do is very, very difficult and we do ask those officers and others in national security roles to take the most difficult decisions to keep all of us safe,” she said.

“We do have to think about how we build confidence in the policing community about their ability to get on with the job that we all need them to do, but also among our communities as well… there is clearly a balance to be struck.”

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