I lived in Minnesota. One of the most liberal places in the country...with Minneapolis/St. Paul being one of the most liberal cities. Their entire government structure is liberal. Their mayor, who elects the police chief is liberal. Heck...the police chief is probably also liberal. You'd think that philosophically Minneapolis would be one of the better cities to be able to handle a system problem like this...right?
We can have the best rules, training, and structure known to man...but if we have police officers that do not respect the value of human life...then we're in trouble. It's going to take a heck of a lot to convince me that with better training and a better system that it would prevent this cop from being a racist killer. You have to change hearts...we have to find a way to prevent those at risk of being killer cops to NOT. If that doesn't happen, then we will continue to struggle. And it will continue to be a struggle in spite of our efforts because now police recruitment became that much more challenging. Who in their right minds would want to be a police officer right now? It's going to be those who struggle to find other work or those LOOKING for power and confrontation. And not to mention...it's an incredibly difficult thing to fight history and people's preconceived biases. There is literally no margin of error, so I'm not even sure that there are reasonable acceptable outcome measures.