Obviously you are unable to differentiate between good cops and bad cops. On the one hand you allow that there are good cops and on the other hand you say the good cops covered for the bad cops.
Wow, do you have a learning disability. Yes, you can be a good cop and cover for a bad cop. Especially when the system doesn't reward you for not covering for them. The problem is collectively ,the organization is designed to protect the bad cops, so the good cops just go along hoping to do some good and get their pensions at some point. This is what needs to change.