Factual error: As the two fast boats start heading up river towards the finale shootout, one boat has its navigation lights reversed. It has a red light on the starboard/right side, and a green light on the port/left side. It should be the other way around. (The lights on the other boat are correct.)
Factual error: Louis Simo gives his son an Etch-A-Sketch while taking him to school, and later when Louis stops by to see his son at his ex-wife's house, his son is playing with the Etch-A-Sketch in his bedroom. Both incidents take place in the summer of 1959. George Reeves died June 16, 1959, hence the investigation. The first Etch-A-Sketch toys were produced on July 12, 1960 and Ohio Art launched the toy in the United States in time for the 1960 holiday season.
Factual error: Text doesn't actually move up a screen, it only appears to; it's really only blinking lights. As such, the improvised scanner wouldn't work, you'd only get a small slice of each line.
Factual error: When Clouseau heard the footsteps of what he thought to be a lady and what we afterwards knew was the Russian trainer, he described how tall she was using the English system of feet and inches, not the metric system, which is used in France.
Factual error: Several characters can be seen playing an Xbox game console, which was not released until 2001, although this movie is set in 1999.
Factual error: When the crowd is gathered outside of the Armstrong homes, there is an extra wearing a "G-Unit" shirt. The movie was set in 1999, but G-Unit didn't launch their clothing line until 2003.
Factual error: When Calvin is examined by the doctor, the doctor notes that he has a large scar on one side, possibly as a result of an appendectomy. The scar is 1) very sloppy; 2) pointing the wrong direction; and 3) on the wrong side of the abdomen for an appendectomy scar.
Factual error: When Josh Hartnett's character pulls up the bathroom tile and find the cash, the bills are labeled "Federal Reserve Notes." Federal Reserve Notes didn't come into use until the 1960s. Back at the time of the Black Dahlia murder, Silver Certificates were in use.
Factual error: Troy has several chains attached to his body, of which two are attached to his Achilles tendons. This is the structure of the leg that allows you to stand and move, so as soon as he ripped them out, he would have fallen over and been unable to walk.
Factual error: The hanging is shown using the "standard drop", with a trapdoor, breaking the neck. This was not introduced until the 19th century (after France had abandoned the gallows for the guillotine), whereas the film is set in the 18th century. In those days the victim was just strung up on the gallows and left to strangulate (the "short drop").
Factual error: In the ending credits, in the cast section, the word "Mobile" is misspelled as "Mobil" five times.
Factual error: When, on their second date, Jenny sucks in air and pulls a cab backwards, the driver spins the tires trying to go forward. The smoke rolling off the tires does not get drawn backwards towards the suction.
Factual error: When Eddie and Jack are in the ambulance you see a curtain over the window behind Jack. This would be a MAJOR infection control/sterility issue and therefore no ambulances have curtains, especially linen.
Factual error: In the parking lot of the race track, as the camera zooms out you can see a new Ford Thunderbird. This is impossible, as the scene takes place in 1979.
Factual error: In one of the opening scenes, when Queenan and Dignam are first interviewing Billy Costigan and Colin individually, Dignam refers to himself as a "staff sergeant." However, the Massachusetts State Police has not had staff sergeants since 1992.
Factual error: While the film is supposedly set in the late 19th Century, the locomotive is oil-fired. The tender carries neither wood nor coal. There is no way the Mexican National Railroad would possess oil-burning locomotives in this time period.
Factual error: The President goes to the G8 summit in Toronto at the end. The G8 is comprised of Canada, United States, Britain, France, Italy, Japan, Germany and Russia. In the room there are a number of non-G8 countries represented.
Factual error: When Chevy is free-falling from the helicopter, his jacket is flapping gently in the breeze. In reality, he would have been falling so fast that his clothes would have been plastered against his back and flapping wildly in the front.
Factual error: When Norah offers Tyler a ride home, she says she is taking him to her special place near Hampden. That place turns out to be at the docks near the Key Bridge, miles away and nowhere near Hampden. (00:47:55)
Factual error: At the end when Ryan Reynolds unplugs Israel and Sparazza, both Israel and Sparazza die. Only Sparazza is on a ventilator. Israel is on a regular oxygen mask, which requires the patient to be breathing without assistance, such as a breathing machine. The type of mask Israel was on is not a life support mechanism that would be affected by being unplugged, as it either runs from O2 from a wall insert or directly from an O2 tank, both of which run without electricity. I work in an ER so I know how O2 systems work.