Let's see if the large liberal cities in the USA can take the necessary step of disbanding their existing police forces and beginning again from scratch along the lines of Scandinavian nations: hire mentally stable and intelligent people, train them properly in a wide range of non-violent methods for tension reduction, and pay them properly so they don't need to take bribes, steal drugs to supplement their income, and all the rest of it. There is zero chance of any meaningful reform short of total disbandment, because serving officers are entirely the wrong kind of people with the wrong kinds of training.