Character mistake: When Riley is laying in the hospital bed and the detective introduces himself he addresses her as "Mrs. Norris." Her name is Riley North.
Character mistake: Bruce Wayne talking to Selina Kyle says that Batman probably saved millions of dollars in property damage alone. When Batman first saw Catwoman he didn't do anything to prevent the property damage before the explosion that she caused.
Character mistake: Being a doctor she leaves Frank the meds he needs to retain his feminity yet she doesn't leave what he needs to stop facial hair. Such things exist.
Character mistake: When Axel is being arrested by the female officers, he says he's been a cop for "thirty years, and black for longer than that." Axel has been a cop for at least 40 years; the first film took place in 1984.
Character mistake: When Fred and Barney are about to be hanged, Betty and Wilma are in the car on their way to save them. Betty calls Wilma 'Willa' instead of Wilma. (01:09:00)
Character mistake: When Greer and Cantor visit Ryan's home after Miller's escape, they state that he was being moved to HMP Albany on the Isle of Wight (correct, given it was a Cat A dispersal prison at the time and regularly used for IRA prisoners) however Greer later states "it happened in Kent, near the channel", which is incorrect. Lymington (as stated by the guards over the radio in the escape scene) is in southern Hampshire - over 90 miles away from Kent and on the other side of the country.
Character mistake: At the meeting in Washington the general says nothing more frightening than a soldier with his M16A1, but they were using M16A2s.
Character mistake: Gail is interviewing Nick on the steps with a tape recorder. You can tell she's holding down the wrong buttons. The record button is in the up position. She's not recording anything.
Character mistake: Aldo tells Rodolfo to reconcile with his son, saying "Sunday is my birthday." Aldo Gucci was born on May 26th, which was not a Sunday in 1980 nor 1981, which is when the scene would take place. (00:31:30)
Character mistake: Whenever Catherine visits the Baroness with young Estella, before she gets murdered, she asks the Baroness for money so that her and Estella could start a new life. Since Estella is being spoken about, the Baroness is aware of her at this point. However, later on in the movie, the Baroness questions John, "What did you think I meant when I said take care of the problem?!" Implying she thought Estella had already been killed when she was a baby.
Character mistake: Nikolai is driving Anna home after the bike went kaputt in the rain, outside the restaurant. Anna towards the end tells him to "take the next right." Both Naomi Watts and Viggo Mortensen are looking left, and keep their eyes there. (00:28:25)
Character mistake: When Erickson is telling Strahm that he no longer has any jurisdiction over the Jigsaw case, he mentions that over a dozen dead bodies were recovered at the meat packing plant, including two cops. There were in fact only 10 dead bodies: Danica Scott, Judge Halden, Timothy Young, Jeff Denlon, Lynn Denlon, Jigsaw, Amanda, Art Blank, Officer Rigg, and Detective Matthews. (00:20:28)
Character mistake: The caption under Shrike's picture in the newspaper that Alma is reading, referring to the circumstances of Shrike's accidental death in a locked safe trick, reads 'Police say famed magician Lionel Shrike vigorously attempting to free himself to no avail.' It should be 'attempted', given he tried and failed, then died, so is unlikely to give it a second go.
Character mistake: At the beginning of the film, Matt arrives at Paddington station in West London. He needs to meet his sister who lives in Chelsea - also in West London. However, for some bizarre reason he gets to her via meeting at Bank station - in east London. It makes no sense why he would make such a convoluted journey. Even if as a tourist he simply doesn't know London well enough to make a more efficient journey, his sister - who lives there - would correct him when arranging a meeting point.
Suggested correction: It's possible his sister knew she was going to be in that area anyway so it would be a convenient place for them to meet. There's no mistake here, just something plausible that isn't, and doesn't need to be, explained.
Character mistake: The conductors on Michael's train repeatedly call the seat check slips "zone stubs." Michael could make this mistake, but no conductor would.
Character mistake: Nicolas Cage looks up the Bing results for Alan Marsh, the journalist he accidentally kind of murdered. The URL of his personal blog, hosted by the newspaper he works for, spells "blog" wrong. (00:55:25)
Character mistake: Dooley refers to his car several times, saying "my 1965 Mustang." It is actually a 1966 Mustang.
Character mistake: When Ben and Stephanie are studying, she repeats the stages of mitosis (which should be prophase, metaphase, anaphase, telophase, with minor differences in the way textbooks divide them) out order; anaphase, metaphase, interphase, prophase. She is supposed to be an A student and Ben, who is also smart and reading from the notes and textbook, says she is right. (00:18:55)
Character mistake: In the morgue, the Captain says the latest victim brings the total up to 16. However, prior to the killing, the news report said there's been 16 victims. This is the 17th victim.
Character mistake: Zeke makes the bold claim that "John Kramer didn't target cops." This is completely and utterly false, and a cop like him should know better. Kramer repeatedly targeted cops. In fact, both "Saw II" and "Saw IV" have officers (Detective Mathews and SWAT Commander Rigg) as Kramer's main target.