Factual error: Whenever the Stars and Stripes is shown it is the modern 50-star version, not the wartime 48-star version as it should be.
Factual error: Chief Superintendent Hilton wears the ribbons of the General Service Medal (awarded for military service in a combat zone, most commonly in Northern Ireland) and the Police Long Service and Good Conduct Medal (awarded for twenty years' service), but not the Golden Jubilee Medal (awarded to all officers with five years' service in 2002), which he would also have. When he reappears in Series 4, he is wearing the Golden Jubilee Medal, Diamond Jubilee Medal (awarded in 2012) and Police Long Service and Good Conduct Medal, which would all be correct, but no longer has the General Service Medal.
Caleidoscope - S2-E4
Character mistake: The chess set in Dr. Pierce's home office is set up incorrectly. When the men are set up properly, each player has a light colored square in the right-hand corner. The board as it appears in the show is set up so that the light-colored square is in each player's left-hand corner. This "beginner" mistake puts the king and queen in the wrong positions.
Factual error: Thomas holds the Gendarmerie rank of Capitaine (by which he is frequently addressed by his subordinates), and thus should wear three horizontal silver bars on his epaulettes. However, in the only scene where his rank is displayed he instead wears the two chevrons of an ordinary gendarme.
Split Second - S2-E2
Revealing mistake: Shortly after Kiera drives the van past the train tracks, we see a few different shots of Travis and Carlos fighting. In a couple of quick shots, Travis' stunt double can be seen. (00:13:00)
Visible crew/equipment: When Rebecca Madsen jumps in her car to pursue the armored truck, as she does a U-turn and takes off at high speed, you can see all the people standing on the side watching the filming. Some even have their phone cameras out videoing it. (00:29:30)