Factual error: A number of the soldiers on the US Army base have haircuts/hairstyles completely against army rules and regulations. This is particularly noticeable given the show is set in the late 90s, when the US Army was much stricter about haircut rules for serving military members. In real life, they wouldn't be allowed to have those hairstyles.
Factual error: Sir John Franklin, Francis Crozier and James Fitzjames all wear a crown over an anchor on their epaulettes, the rank badge for a captain with over three years in rank. This is correct for Franklin and Crozier, but Fitzjames only held the rank of commander, and should therefore only be wearing an anchor on his epaulettes.
Protect Her - S1-E1
Factual error: When Jules and Hannah are talking about the financial shenanigans at Owen's firm, Jules says that the owner of Owen's company had fraudulently driven up the price of the stock before the IPO. This is impossible. The IPO is the first time the shares become tradeable.
Factual error: When the stolen freight train is braking, the air pipe becomes disconnected. This should trigger the brakes on the train, but the train keeps going with no brakes. When the train is being slowed with no brakes working, why are there sparks coming from all wheels on the train? (00:32:00 - 00:38:00)
Factual error: The Royal Navy sailors are shown with just 'HMS' on their cap tallies. This was only seen in the Second World War for security reasons. In peacetime, the tally bears the name of the ship or shore establishment to which the rating is assigned.
Factual error: S2 E3 Along Came a Spider - Captain Carrillo is target shooting with a hand weapon. She empties the magazine, but she catches the magazine and hands it to her ranger partner instead of letting the empty magazine fall to the ground. As a trained military officer and training with special operators, catching an empty magazine is an extremely bad habit and practice, which is a big no-no. (00:40:23)
Los Moscos - S2-E1
Factual error: Outside the church headquarters where Norman has his stroke is a board saying 'United Methodist Church'. The UMC didn't come into existence until 1968. It was the Methodist Episcopal Church in the 1930s.
The Last of the Cybernauts ...?? - S1-E3
Factual error: When Kane pushes the Range Rover into Gambit, the hand print in the Range Rover's boot looks more like it was made in clay, not the steel panel of a car (which would have simply dented).
Factual error: Luka's military officer cap isn't a Russian cap, it is a Hungarian police cap. The Russian cap is bigger.
Factual error: Constantine's driving licence is shown - it's a UK licence, but no. 7 where his signature should be is blank, and no. 8 where his full address should be simply says "England, United Kingdom." Both are printed onto the licence when it's issued - without that info it would never be issued in the first place. And it's not a fake, because why would he have a fake licence with his real information on it? It's just an incomplete prop.
Factual error: Despite taking place in Massachusetts and many of the cars having Massachusetts license plates, none of the vehicles has the required annual inspection sticker on the lower part of the passenger side of the windshield.
Factual error: A British soldier in 1940 says he was educated at the University of Warwick. The university wasn't founded until 1965.
Factual error: In Massachusetts, Atticus, Leti and George are attacked by the local sheriff and his deputies, who are patrolling the county roads. In Massachusetts, sheriffs run the county jails, but they do not (and did not) handle routine policing, which is the responsibility only of municipal police departments.
Episode #1.6 - S1-E6
Factual error: In Episode 6, Vincent comes out of his apartment building and before he reaches the curb, and has a chance to hail a cab, one is waiting for him. There was no ability to book a yellow cab in the 1980s.
Factual error: Broken Bow is in the southeastern corner of Oklahoma. US 60 is shown here, but actually cuts across the northern part of the state. (00:09:30)