It takes a lot of confidence to make a movie where every single character is pretty much an idiot, a scr3w-up or a full-on loser. In order to then avoid making a broad farce, it requires the writing, the acting, the directing - something - to be so well done that it remains believable and we maintain our interest.
Lumet's camera work gets so close to his characters it's clear he's confident his actors can pull it off. And they do - Connery, Walken, Balsam, Cannon, King - they really shine.
Various levels of police monitor, tape, investigate, and rush in like cavalry. But it's never clear whether they'll accomplish anything b/c they're so busy tripping over their own feet. I found the Third Act to be quite comical in this regard.
It's quite clear from the very last scene what Lumet was trying to say about the surveillance state and police methods.
