Character mistake: When discussing the new Pope's name (Luke) at the end of the film, Langdon says: "There have been many Marks and Johns, but never a Luke." In fact, though there have been 23 Pope Johns, there has only been one Pope Mark - reigning for 9 months in 336.
Character mistake: When Malloy first visits Frannie in her apartment, he says the girl was killed on the 15th, but when Frannie is in the cop car for the first time, Malloy's partner says it was the 11th.
Character mistake: Amanda's lawyer says several times she'll go to the gas chamber if found guilty - once to her, once to the prosecutor and once to the jury. Oklahoma doesn't use, and never has used, the gas chamber for executions. (00:15:00 - 01:16:00)
Character mistake: The sign Riggs holds outside the South African Embassy has a spelling mistake. The sign says "end apartheid now" but the word apartheid is misspelt as "aparthied".
Character mistake: Near the end, just before Derek and Danny depart at Danny's high school, Derek says to his brother "I saw a car cruising by the house last night when I pulled out of there with Seth." The car that was shown driving by their house the previous night was in a brief scene right after Derek and Danny took down all of their nazi posters, and before Derek took a shower. He had not just 'pulled out of there with Seth.' The last time he had seen Seth at this point in the movie was at Cameron's party where Seth had almost shot him.
Suggested correction: Just because Derek says to Danny that he saw a car driving by their house when he left with Seth and a black car drove by later in the movie doesn't mean that this is the car Derek was referring to. There are many possibilities to explain what Derek was referring to (perhaps he was paranoid and saw an ordinary car driving by that he thought was scoping their apartment out) but it doesn't mean that the black car is the one he was referring to when he warned Danny.
Character mistake: After the first attempt by the kidnappers to get the ransom money, they tell the FBI to bring the money behind the Foo Chow restaurant. Clive gives Carter and Lee the exact same destination. Why in the world would kidnappers give the FBI a drop-off location exactly where they are based?
Character mistake: Close to the end, Madison is looking over the H.A.L.O. list on her laptop. When Dylan's profile pops up, her last name, Saunders, is misspelled as Sanders.
Character mistake: Near the end of the movie, John's wife calls one of his colleagues and says, "Jad, it's Laura, John needs a favour." Her character's name is Lara. (02:08:30)
Character mistake: When Detective Welles is searching for Naomi in the Police Computer System he types "Naomi, Cozier" which is backwards - he should have searched "Cozier, Naomi" or skipped the comma entirely. (00:58:20)
Character mistake: Nic Cage says "At 4 and a half months, the human fetus has a reptile's tail". This is totally incorrect. A human fetus has a tail-like structure between 4 and 7 weeks, not months, and it is little more than a mass of flesh which helps the muscular structure of the backbone develop before being absorbed for use in the formation of the legs and hips. (01:28:50)
Character mistake: Buffalo Bill's revolver is a double action, meaning did not need to cock his gun before firing it (you only need to do so with single-action revolvers. Cocking a double-action just makes the next trigger pull easier.) He could've just shot Starling. His stupidity got him killed.
Character mistake: At the very beginning of the film, when Hannibal Lecter is serving dinner to his guests, one diner asks "what is this divine looking amuse-bouche" when she and the other guests have a full plate of food. An amuse-bouche is a single bite of food meant to be served at the beginning of a meal, not a plate full of food. Lecter's guests would be better educated.
Character mistake: Early in the movie Cary Grant is on the beach and is told he has a phone call. While conversing with Bertani, Cary Grant has the handset backwards - he is speaking into the earpiece and listening to the mouthpiece where the chord is attached.
Character mistake: The bank robbers send out a hostage and put a drawer around his neck with a note. The drawer is bugged and the bank robbers can monitor the police. The police just leave the drawer lying around on the table for half of the movie inside their mobile headquarters. This drawer should be in a forensic laboratory being checked for fingerprints and similar.
Character mistake: Once Santino and Ares find John again in the hall of mirrors, John is fighting two of the grunt men that came in with Ares and kills them. Both of which had light assault rifles and weapons on them. John and Ares proceed to empty their pistols out at each other before she runs off with Santino. John then throws his empty pistol away and gets up to pursue his target unarmed and while limping. It is unreasonable to think that someone with his skill and training and experience would not take two seconds to reach down and pick up one of the guns dropped by the two men he just killed before chasing after his target, especially given the highly trained body guard with him accompanying his target. As well as probable encounters with more grunts. To add to this, he was seen doing just this moments before when he had limited ammo and each time he'd down a few enemies he would pick up one of their guns and continue. (01:41:30)
Character mistake: Jungle Julia refers several times to Dave Dee, Dozy, Beaky, Mitch and Tich, instead of Mick and Tich.
Character mistake: Candy's full name is Candace Washington, which is referred to in the movie, yet when she is released early from prison, the correction officer calls her Candace Collins.
Character mistake: In the scene where Detective Fanning and the other cops are investigating the first murder, one cop tosses a shell casing in a baggie out the window to Fanning. The cop then remarks, "You can still smell the cordite." This is incorrect because cordite has not been used as cartridge propellant since approximately the end of World War II.
Character mistake: You'd think prison guards on Death Row would have known a little more about safe restraints, the way they bind and gag Percy could eventually kill him. They stuff a handkerchief all the way into his mouth, then tape his mouth closed. The gag reflex could suck the handkerchief into his windpipe and suffocate him in about three or four minutes. Even if he might be able to find away around the danger of suffocation the fact remains that no trained, experienced prison guard is ever going to restrain someone in that way.
Suggested correction: Not everyone even has a gag reflex, and it is easy, though not comfortable to push the handkerchief forward into the mouth with the tongue. You can see Percy breathing through his nose, so he's not running out of air. The other guards had no intention of leaving him in the cell for a long time, only long enough to teach him a lesson.
It doesn't matter what he "might" be able to do, or even if he could push the handkerchief forward. That's not the mistake. A trained, experienced prison guard would not restrain someone like that. Never.
Again, what might or might not have happened is irrelevant. No skilled, trained, experienced prison guard would apply a gag in this way.
Character mistake: When Spoken Reasons describes Kaitlin Olson, he says she has brown eyes. She has blue/green eyes.