It's true. It's the dude nearest the camera, you can see his empty hand through the windscreen. You gotta pause the film to see it though.

At 1:36:08, after Joey shoots the gun to get his father's attention, the cops get behind their cars, and just as the cop on the bullhorn is shouting, "Lieutenant LaMarca, if you can signal to us your location" A cop in a foreground car is pointing his hand out the window as though holding a gun, but there's no gun!
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Where exactly is this supposed to happen? I just went through that scene 4 times frame by frame, from the time Joey says, "Don't worry, your friends out there will." until the cops call for cease fire, and all of the cops have guns.

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