Continuity mistake: When Pierce's wife is walking in her auto shop they pan down to show her red Louboutin heels, then they cut to her walking in her office, and when they show her shoes again they have a tan sole.
Factual error: The old percussion double barrel shotgun is firing modern shotgun shells, which would never work or fit in that gun, and furthermore are also made of plastic, wrong for the era.
Continuity mistake: At the beginning Ava shoots the man's phone out of his hand through the car window. When the car drives away all the windows are intact.
Factual error: The Corvette owned by Bentwood is not a Z06 as shown in the movie. It is a 2014 C7 Stingray and can be identified by the Stingray logo on the side of the car.
Continuity mistake: SPOILERS: During the final scene, when Samuel L. Jackson is "puppeted" to lift his arm up to make it look like he's pointing a gun at the SWAT team, the number of laser-sights visible on his chest changes between cuts. In the wide-shot, there's only three, but when it punches into a close-up, suddenly there are five.
Continuity mistake: A pile of drugs gets blasted up with powder flying everywhere yet there's none on the ground seconds later.
Factual error: SPOILERS! While the ending of Al being arrested for murder at his own wedding is dramatic and cathartic, it wouldn't have happened that way. There's no way that the cops would have known to search the wooded area near the cabin; they would have needed to find physical evidence linking the cabin to Al; they would have needed to establish that Al had no alibi for the time in question; etc. None of that would have happened that quickly or that quietly.
Continuity mistake: When Marcus sees his baby grandson, a nurse in the background is picking up a white diaper. In the close-up the diaper is now blue.
Factual error: While on the fishing boat, the flag flown has 50 stars, while the movie is set in 1941. The US didn't have 50 states, and thus that flag, until 1959. (00:30:08)
Factual error: The USMC Embassy Guard is an enlisted Marine Sgt. He is wearing a Commissioned USMC Officer's cover (hat) that has gold braid and gold oak leaf motifs on the visor. (01:20:15)
Factual error: The Blackledges' car has a license plate that starts with 34. Montana uses the first two numbers on their plates to identify the county that the driver lives in. 34 is the number for Sheridan County which is in northeastern Montana where there are no mountains in sight, but the Blackledge ranch is set near the foothills of a mountain range as you would see in western Montana.
Visible crew/equipment: While on the Genesis, when Robin finds Frank she asks if he's bulletproof, then Alpha 5 contacts ops to open hatch 26, and as Frank and Robin walk over to the monitor, a white T-mark is visible on the floor. (01:20:40)
Character mistake: Bart is sitting on a bench outside the hotel. After Detective Espada talks to the Mercer hotel manager/owner, he goes to talk to Bart. Bart has blood on both hands and lower left sleeve. Detective Espada is supposed to be investigating a fresh murder case that puts Bart at the scene, but he does not confiscate Bart's bloody clothes, conduct a gun powder test on Bart's hands to check for residue, or take him to the police station for formal questioning. Espada did not follow police protocol. (00:17:36)
Factual error: Apex, played by Robert Maillet (a retired professional wrestler 6'11" and 350 pounds), forcefully slams Becky (played by 5' tall fifteen-year-old Lulu Wilson who probably weighs under 100 pounds) horizontally with her back hitting the ground from waist-high yet Becky is able to get up with no incapacitating injury that would be expected. Becky also manages to brutally kill him (as well as the three other neo-Nazis).
Continuity mistake: In the opening scene, the blue car is parked on the far right of the screen or at least one car length from the doctor's front door. Dr. Huggins says goodbye to the couple with the baby, who walk toward their car. After the burglars-to-be (turned robbers) are shown watching from a distance, the camera returns to the doctor's front door. The blue car is now near the center of the screen and it drives away toward the right of the screen - going past the place it had been parked.
Factual error: TV reporters said "home invasions" and mentioned trying to find the people who were responsible for the "70 robberies." Lance (in prison), was talking to a woman who was going to write a book and told her he got "twelve years" for "fifteen counts of robbery and vandalism." The crime Lance and the rest of the group were committing fits the legal definition of "burglary" in Illinois (basically, entering an occupied structure with the intent to commit a felony or theft inside; the structure does not have to be occupied at the time of the act). Because there happened to be someone at home during their last (intended) "burglary", this offense would be classified as a "robbery."
Other mistake: Fran is unconscious near a gas stove as Marla comes to save her. As Marla is trying to move her, Fran moves her leg even though she is supposed to be unconscious.
Continuity mistake: Bernice's bangs go back and forth between having a small section separated from the rest to not separated. Before she kisses Thomas, her bangs are separated, but combed together when they are done kissing. (00:21:56)
Other mistake: Rayburn pulled an arrow out of his chest - and without much blood gushing out. The rather small amount of blood on the towel and Rayburn's ability to go about business as though he had not been injured is unrealistic and absurd. (00:27:00)
Other mistake: When Lomito was holding the little green ball with the smiley face on it, her flashlight was shining on her fingers/fingernails - all of which were long and manicured. The length of her fake fingernails - even if they did not exceed the department's policy on maximum length, such as one-fourth inch past the fingertip - probably were long enough to interfere with her ability to quickly put her finger on her pistol's trigger and shoot; the length interfered with her ability to perform her duties. (00:31:25)