A mate of mine who was in the police once stopped a local footballer who was driving like a lunatic. Footballer winds down window, gives my mate a smug grin and says "Do you know who I am?"
My mate replied "As a matter of fact sir I do. Which means I shouldn't have any problems identifying you in court."
That wiped the smile off his face
He always said that "Do you know who I am?" was like red rag to a bull.