So what would have happened if Mark Duggan had been shot in China – assuming that the shooting had the same outcome, ie major outbreaks of rioting in major cities, including especially the capital?
Given that last, the answer is simple: the officers would have been punished. Ostensibly for the shooting, but really as a riot control measure. It would also have happened fast, as soon as it became apparent that the streets couldn’t be cleared by main force, as a means of taking the impetus out of the proceedings. Officials and law enforcement officers are sometimes removed from office amid huge publicity in mass incidents and then quietly re-instated or transferred when all the fuss has died down. But one of the metrics on which officials are graded in China is on maintenance of public order (until recently: Xi is apparently considering dropping this). So on this occasion there would be a lot of angry cadre wondering why the hell they got a black mark on their file because a couple of cops shot someone in the capital. They too would need to be satisfied.
Obviously, this would have nothing to do with any process of law or justice. It’s mainly to do with how an authoritarian system channels sporadic outbreaks of potentially destabilising discontent into a kind of steady-state ‘conversation of violence’ between the authorities and sections of the public. It’s not a state of affairs that Beijing is necessarily unhappy with. If the PRC Embassy on Portland Place sent reports on the Duggan affair back to Beijing I suspect it would critique the ‘poor handling’ of the affair by the British government.