The Metropolitan police and the Greater Manchester force have been urged to make clear whether or not the use of stun guns against black men by officers this week was proportionate and reasonable. Desmond Mombeyarara, 34, was shot with a stun gun by police near Manchester on Wednesday evening in front of his distressed young son after officers stopped him for allegedly speeding. A video of the incident went viral on social media and sparked an outcry, before it then emerged that a man in his 20s had been left with “life-changing injuries” on Monday after he was shot with a stun gun in north London. He was found in possession of cannabis. StopWatch, a coalition that promotes fair and accountable policing, has written to the Met deputy assistant commissioner, Lucy D’Orsi, and the Greater Manchester chief constable, Ian Hopkins, saying it was “deeply disturbed” by footage showing Mombeyarara falling on to a petrol station forecourt and being subject to a further Tasering once prone. The coalition called for police to urgently address fears among members of the public – particularly black, Asian and minority ethnic people – about whether they are safe from the “unnecessary, disproportionate, and unreasonable” use of stun guns. “The National Decision Model states that officers will only use force to the extent that it is necessary, proportionate and reasonable,” the chief executive, Katrina Ffrench, wrote. “We would be grateful if you would inform us of the steps being taken by the police service to assess whether these standards were met in the incidents described above and, if they were not, what action will be taken as a result. “In view of these very serious incidents, occurring within a matter of days of one another, we also request that the National Police Chiefs’ Council and the National Taser Stakeholder Advisory Group reconsider, as a matter of urgency, how members of the public, particularly those from black and minority ethnic communities, are to be protected from the unnecessary, disproportionate, and unreasonable use of Taser. “The coronavirus pandemic is putting huge strain on our communities and public services. Under these circumstances, it is especially important that the police service attends to the need to maintain the trust and confidence of the public. “The kind of incidents we have seen recently involving the use of Tasers threaten to undermine this trust, particularly among impacted communities, and – as we know only too well – have the potential to spark serious public disorder.” The police watchdog is investigating the conduct of officers involved in both incidents, but there are fears that the outcomes could take months to reach and protesters demanded justice on Saturday. DCS Treena Fleming, of the Met, said on Saturday afternoon: “All police officers are fully aware that they will be asked to account for their actions – officers are not exempt from the law and we would not wish to be. Three officers have been informed they are under investigation and placed on local restrictions. “My senior leadership team and I are working hard to engage fully with our community partners, key stakeholders and the local authority. We are speaking with them and listening to their views.” GMP Supt Mark Kenny said on Sunday: “There has rightly been a lot of concern about the officers, and rightly this will be investigated to establish if their conduct was lawful and followed correct procedures. “The matter was referred voluntarily to the Independent Office for Police Conduct (IOPC) by the GMP. This is to ensure complete transparency … Officers must abide by the law, and this includes when using force.” Analysis of Home Office figures shows stun guns were used against black people in England and Wales at a rate almost eight times greater than against white people in 2018-19, with their use generally rising 39% last year. StopWatch was among a number of civil society groups to quit the National Police Chiefs’ Council’s independent Taser advisory group over concerns that no meaningful action was being taken to address the racial disproportionality. The coalition said it has not yet received a response to its resignation letter on 24 March.