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

Bart: Take him away, boys.
Chief Wiggum: Hey, I'm the chief here! Bake him away, toys.
Lou: What'd you say, chief?
Chief Wiggum: Do what the kid said.

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.

The Simpsons Quotes

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!

Mr. Burns: Oh, and one more thing: you must find the jade monkey before the next full moon.
Smithers Actually sir, we found the jade monkey. It was in your glove compartment.
Mr. Burns: And the road maps, and ice scraper?
Smithers: They were in there too, sir.
Mr. Burns: Excellent! It's all falling into place...