Continuity mistake: When Carrie Bufalino says she wants to stop for a smoke she is sitting on the right side in the car, behind the driver. When they stop she gets out from the left side. (00:21:05)
Continuity mistake: When a man attacks Hoffa in court, Hoffa's son attacks him, then in the next shot he is not up from his chair. (01:22:47)
Continuity mistake: The green late 1960s Cadillac Eldorado that gets shot up is two different cars. The first car shown is a 1967 model while the other car is from a later model year with circular side marker lamps. (01:33:00 - 01:34:30)
Continuity mistake: After Joey Gallo messes with Russel on his birthday in the night club, Frank is ordered to kill him in a small restaurant in little Italy. Frank succeeds and Gallo seems dead, being shot multiple times on the ground and while running. Later in the movie, in the "Frank Appreciation Gala" scene, we can see Joey Gallo as one of the guests, very much alive and happy to be there for Frank. (01:42:54 - 02:13:01)
Continuity mistake: When Frank calls Jo after Jimmy's death Frank has different reactions in different shots. Obviously, the scene is shot more than once and while editing they made the mistake and couldn't cut correctly. (02:52:10)
Continuity mistake: When Hoffa is angry at the meeting bitching about the Kennedys Frank exits and puts his coat on. The collar is raised in the front shot and lowered in the angle shot from behind.
Continuity mistake: When Russ and Frank are in the hotel pool the woman in the left is holding a cigarette. In the close-up it swaps to a lemonade. Then in the wide angle it swaps back to a cigarette.
Continuity mistake: When Frank walks in the restaurant to meet Angelo Bruno, he takes a sip, puts the glass down and says "sit down, Frank." From the opposite angle he is lowering his glass again.
Continuity mistake: When Frank tries to calm down Crazy Joe at the club after the Don Rickles show, Joe turns away twice.
Continuity mistake: When DeNiro kills Hoffa in the house, he is wearing white socks. In the later scene when they are going to place the box containing Hoffa in the incinerator, he is wearing black socks.
Continuity mistake: When Jimmy is sitting with Frank at the restaurant complaining about the fact that Tony Pro is late, we see Frank holding a Coca-Cola bottle with the right hand, but in the next shot the hand disappears from the table and stays down resting on the chair.
Continuity mistake: When the Sheeran's and the Bufalinos get in the car in Pittston, Carrie gets in on the left. In the next scene as they're starting the trip, Carrie is sitting on the right.
Continuity mistake: During the car trip to the wedding they were driving a 1978 Lincoln Town Car until they stopped at Howard Johnson's; after HoJos they were driving a 1975/76 Lincoln Continental: amongst other differences the front grills are different in those years.
Continuity mistake: When Jimmy is in prison, eating a dish of ice cream while having a conversation with Tony Pro, the amount of ice cream in the dish keeps changing: there's more ice cream, there's less ice cream, there's more. Every shot the amount increases, then decreases next shot. Also, sometimes you can see a cherry stem in the dish and sometimes there's no cherry stem.
Continuity mistake: When Frank walks up to the plane the nose is facing left. When the pilot gets on and closes the door and window the plane is favoring more center on the tower.
Continuity mistake: After Don Rickles jokes about the Italians, Crazy Joe raises slightly and shouts at him. From the opposite angle he is standing up.
Continuity mistake: When Pro meets Hoffa in Miami the cloud of smoke from his cigar appears/disappears randomly depending on the shot.
Continuity mistake: When Hoffa is eating an ice cream and JFK is shot he stands up and the spoon swaps between being in a 9 o'clock position to a 12.
Chosen answer: First off his name was Chuckie O'Brian. Jimmy Hoffa wasn't his biological father, he was more in the nature of a foster father. Second, he probably knew what happened. What was Chuckie going to do? It was a sanctioned hit. And if he went to the police he would have ended up the same as Jimmy Hoffa. They put him in the middle of it to keep him quiet. If he goes after the people who did it, he's as good as dead. If he talks he could end up in jail with them, and the mafia will probably kill him anyway.