Actually states do not have the ability to prosecute police to the extent we would think they do. Police chiefs cannot even fire police. Investigating a police officer for wrongDoing or firing a police officer for wrongdoing must follow specific protocols in Union contracts that are put in place specifically to make holding the police accountable a bureaucratic nightmare.
>>TeaDru+(OP)
I think there's a good argument to be made that the one of the most important steps to solve the US police brutality and unaccountability problem should be to declare Police Unions to be illegal.