Lou the Cop is one of Wiggum's two frequently used police officers.  Lou definitely seems to be the hardest working and most competent of the cops.

Lou Quotes

Chief Wiggum: Hold it right there, Switches of Eastwick.
Lou: Switches of Eastwick?
Chief Wiggum: I don't want to censor myself. That's how creativity dies.

Chief Wiggum: Who are you, the rules police?
Lou: No, we are the police police.

The Simpsons Quotes

Principal Skinner: You're not supposed to be able to get outside our network.
Nelson: You shouldn't have made your password, "password".
Principal Skinner: It was the name of the street I grew up on, Password Drive.

Homer: (Wearing glasses) The sum of the square roots of any two sides of an isosceles triangle is equal to the square root of the remaining side!
Man: (From inside a bathroom stall.) That's a right triangle, you idiot!
Homer: D'oh!