Revealing mistake: In scene at the brothel, with the senator and the dead prostitute, the supposedly dead body is breathing in the last shot of her, just after Tom Hagen says "it'll be as if she never existed". (01:15:30)
Revealing mistake: Watch carefully as the statue falls on the bartender. It barely touches his chest and rests on his left thigh. As the bartender slumps dead you can see a wide open gap between his whole upper body and the statue. Even if it crushed his thigh it would not have killed him so quickly. When the bartender slumps down the statue rocks freely as he brushes against it; obviously a styrofoam replica.
Revealing mistake: When Crewe dumps the car in the river, you can see the wire attached to it that was used to pull it out of the water. Burt Reynolds mentions it on the DVD commentary.
Revealing mistake: When the Charger hits the red truck, the truck turns over with the assistance of a 'pipe cannon' (note the sudden eruption of white smoke from under the truck). This device is like a large gun, pointed down that fires a cylindrical wooden 'bullet' at the ground, and the pressure behind it forces one side of the truck upward, causing the flip. Evidence of its use is seen when the passing cop drives away and in the street is a perfectly circular 'dent' in the asphalt with a burn mark surrounding it. (01:12:50 - 01:16:20)
Suggested correction: A cannon roll uses a large device, usually a metal pipe that is pointed down, but it does not fire a "bullet" wooden or otherwise. It is just the force of the explosive charge focused downwards that causes the cars to roll over.
A cannon roll shoots out a wooden log to flip a vehicle, it's not just shooting out air.
This is just nonsense, a wooden log would be too dangerous to use, would be highly conspicuous on screen, and would take up room inside a vehicle.
Then you don't know how they use to do car stunts. It does take up room, but even modern methods do. Cars have to be modified heavily and of course it's dangerous, they're flipping a car with a driver inside. Film makers do everything they can to avoid the stunt car from being detected (just the same way they do everything that can to avoid a dummy being detected). Here's a article that talks about car stunts before the pneumatic flipper. Https://www.caranddriver.com/news/a15364815/the-inside-story-of-the-academy-award-winning-car-inversion-device-or-how-to-flip-cars-real-good/.
Bishop73 is right. For example, from Raiders of the Lost Ark: https://www.moviemistakes.com/picture6238.
Revealing mistake: When Mr. Green pulls out of 28th Street, we see him disengage the "Dead Man's Feature" (by pressing down on the throttle with his hand). However, he does not actually move the control lever to make the train move. In that position, the train is at "idle" and will not accelerate.
Revealing mistake: In the office tower after the quake there is a panic and workers rush down the stairs only to find them fallen away. After two women fall to their death a man is left hanging on a girder, but falls onto a giant piece of glass. Look at the top of the frame and you will see the airbag shooting our from under it.
Revealing mistake: When the co-pilot gets sucked out of the plane, it's obviously a dummy.
Revealing mistake: When Clint Eastwood and Jeff Bridges are being chased by George Kennedy and his partner, Bridges is driving off the dirt road down and embankment and you can clearly see that in the passenger seat is a faceless dummy instead of Eastwood or another stunt man.
Revealing mistake: In most scenes where you see the group's van, it has the year letter on the number plate covered up. But when they park outside their manager's office, you can see that it has an F registration dating from 1967/8, meaning it would be too modern for the early part of the film.
Revealing mistake: Whilst being followed by Celine, Julie walks up a small flight of steps. When this happens, a blue car can be seen turning around a corner and driving past the camera. Just as Julie walks into frame, the driver of the blue car can be seen looking at the camera just as he drives past it. (00:05:58)
Revealing mistake: When Butt falls behind the suitcases, a mattress to soften the fall is visible.