What you are describing is the London Metropolitan Police which are regarded as one of the worlds best managed police forces, where the average bobby are unarmed and where the code of conduct focus on public service.

It;s also worth noting that when the UK faced a similar problem with an undiverse militarized police force in northern Ireland they did this https://cain.ulster.ac.uk/issues/police/patten/recommend.htm and launched a bunch of investigation(the Stevens enquiries) into past crimes of the Royal Ulster Constabulary.

The problem in America blocking any meaningful solutions to genuine problems is the collective denial the American middle class have towards past sins and current systematic problems with the American way not that it's a new problem that have never been solved before.