Can Cops drive over the speed limit?

Today I saw a cop driving way over the speed limit and his lights were not even flashing.

This is not the first time I saw this but I question my self every single time I see them passing by. Can Cops drive over the speed limit? Then quickly my mind answer me…. DAH!!!!! who is gonna give them a ticket. lol

I told my brother I am gonna follow him and you make that siren sound and lets give him a ticket for driving toooooo fast. lol

What you think? Should a normal citizen can give police car a ticket for driving over the speed limit?