I think most cops are good decent people trying to do their job, but there are definitely some that are corrupt and some that are prejudice. This is because, cops are usually not very well educated. Although there are university graduated police officers out there, most university graduated cops, would belong to advance agency such as FBI and Homeland security. Ordinary cops, don't have that level of training, they only have one year training, their training is only of community college standard. So, they are not very highly educated in policing, in addition, because the police force do not set their standard to all officers must be university graduated in policing, but only community college graduate standard, it mean some people who became cops, sign up because they are too stupid to make it into college and as we know from high school, most of the people who do bad in school, are the trouble makers. If all cops need to have at least a Bachelor degree in policing or has both a community college standard training in policing and a Bachelor degree in some field relevant to policing (e.g. psychology, forensic). It would definitely increase the standard of cops, and issue of police brutality would decrease. But we also need to consider the fact, smart people are not necessary very tough and the police still need extreme tough units such as SWAT. These smarter police officers with university qualification might be tough enough to endure the training to become ordinary police officer, but how many of them are they tough enough to be SWAT? If we take a look at SWAT training, those who join, are already really tough cops and even then half of them, didn't make the cut. So, if we all cops need to be university graduates, we must also make sure, amount them, there are enough people that are good enough to make the cut into elite units, such as SWAT and that is to find a way to encourage university graduates to join the police force and encourage high school graduate to study a bachelor in policing in college. Method of doing so, might be increase the pay of the police force. I know there are a lot of very just people, whom set their mind on been police officers when they grew up (I was one myself) but once they reach high school, they need to consider the reality of the high stress and high danger of been a police officer, yet seriously under paid. This would turn so many young boys, that wanted to be police officers, away from the job. Also, those who study a Bachelor degree in policing, should first finish one year of the same community college standard police training, to make sure they are up to the job, then start working as part time cops, so, to make sure they are tough enough, while studying for their university degree in policing, to make sure they are tough enough for the job. The government should pay for their entire university degree in policing, but to train a university graduate cop cost a lot of money, so, after they graduate, they must remain as a police officer for a minimum of ten years.
If you just want to deal with the issue of police brutality towards blacks and not the wider problem, there is a simpler issue, encourage more black people to join the police force.