Why does Hollywood portray cops as severe criminals when that is not reality?

There are so many movies involving police corruption. Some off of the top of my head, (An Innocent Man, Above the Law, Walking Tall, Ransom, Training Day, and American Gangster, which said 75% of the drug enforcement agency was convicted of drug bribes which is completely false). Being involved in real-life scenarios, whether you love or hate cops, they are honorable and law-abiding 99.9% of the time. Why does Hollywood always portray them as the bad guys? Hatred and for good ratings?|||Same reason they mock everything that is good. They are despicable people with money.|||Because there hollywood. Nothing is real and they think it is....