Can you help me identify a movie? In which film did someone take a Polaroid photo from underneath a security camera then stick the photo in from of the camera with chewing gum? I believe that it was a gang robbing a place for some reason. The gum eventually came unstuck and the photo fell off, alerting the security guards

I've seen this done on an advert. Not seen the film though. Mmm, clever.

I don't know the movie you mean although I think they did it in an episode of the A-Team.
In the film Entrapment they freeze frame/pause the security camera so that it keeps showing the same picture.