The murder charge brought against Martyn Blake sparked fury among firearms officers with dozens downing tools in apparent protest and the Army being put on standby to plug the gap.
A fierce debate erupted about how police marksmen should be held to account after taking a fatal shot, with warnings that officers could be put off volunteering to undergo firearms training for fear of being embroiled in lengthy legal battles.
Prosecutors announced that Mr Blake would be charged with murder over the fatal shooting of Chris Kaba in September last year.
Following a trial at the Old Bailey, a jury cleared Blake of his murder.
In the wake of the decision, one of the country’s most senior police officers, Metropolitan Police Commissioner Sir Mark Rowley, claimed in an interview with The Sun that marksmen would prefer to confront a terrorist than a gangland criminal because there would be less of a legal backlash.
He also took aim at justice campaign groups, telling the newspaper: “One thing that’s really startled me is I’ve had some of our firearms officers say to me they would rather end up confronting on the streets a well-trained terrorist than a gangster.
“Because even though they would face far more personal danger with the terrorist, they believe they’d get a fair hearing in terms of the legal processes that follow.
“Whereas with a gangster, they feel that campaign groups can influence accountability in a way that leads to something that’s unbalanced and lasts forever.”
Then-home secretary Suella Braverman commissioned a government review of how firearms officers should be held to account, with suggestions that officers would quit their roles if they were dissatisfied with the outcome.
Simon Chesterman, who is the armed policing lead for the National Police Chiefs’ Council, warned that “significant numbers” of officers could step back.
Armed officers are not paid extra for undertaking the role carrying weapons and do so on a voluntary basis, meaning they can down tools, known as handing in their tickets, if they wish.
The length of time taken to resolve legal and disciplinary proceedings involving police officers following deaths in custody has also been criticised.
In a separate case, an armed officer known as W80, who shot Jermaine Baker, 28, during a foiled prison break in 2015 is still yet to face a disciplinary hearing.
Prosecutors said in 2017 that there was insufficient evidence to bring criminal charges, but a legal battle has rumbled on between the officer, supported by Met bosses, and watchdog the Independent Office for Police Conduct (IOPC), over whether he should face disciplinary proceedings.
Last year, the Supreme Court ruled in favour of the IOPC, meaning that he should, and in November last year the Met agreed that a hearing would take place “at the earliest opportunity”. No date has yet been set.
