Are the Police corrupt?

I had gone shopping today. (Oh, I hate to go out nowadays without a cameramobile phone) There is a watering hole just across the road where I stay. Today I saw a police van standing beside it. A posh one. A Qualis. It watered its pockets and went away. I thought I could get the number plate of the vehicle, but then I saw a few people watching me. I gave up the idea. Probably I didn't have the balls?!!
Are the police corrupt? Well, I guess the shopkeeper too was corrupt. He wanted to continue with his business.
If I speak up I will probably end up alienating all the people who frequent that place. Well, I speak up and complain but when graft runs in the blood what can you do? The policeman may be shouted at for today.
What about tomorrow? I may go away, however, what about these people? They need to stay on.