Context

This misquoted line is spoken by Gold Hat, played by Alfonso Bedoya, in the film The Treasure of the Sierra Madre, directed by John Huston (1948).

The Treasure of the Sierra Madre teaches us a valuable lesson: always ask for identification. Yes, there's some sort of moral about greed or something, but the lesson that has stood the test of time is to ask anyone who says he is a cop for his badge. And if he says, "I don't have to show you any stinkin' badges," not only is he kind of misquoting a famous movie, but he is either not a cop or is a terrible one.

The actual full line is, "Badges? We ain't got no badges. We don't need no badges! I don't have to show you any stinkin' badges!" We understand why it's been shortened to a much pithier statement over the years.

Where you've heard it

Perhaps the most famous reference to this misquote is from Troop Beverly Hills. Those scouts don't need any stinkin' patches.