Factual error: At the beginning, the screen shows that the year is 1988 in Corpus Christi, TX, then the camera pans into Selena and her sister eating tacos when their friend Jake arrives wearing an Arizona Diamondbacks shirt. The Diamondbacks did not exist in 1988. Phoenix was awarded a Major League Baseball expansion team in 1995 and the Diamondbacks made their debut in 1998, 10 years after this scene takes place. (00:00:30)
Factual error: The Columbia paramilitary is seen throughout the 2nd season carrying M4's. The M4 configuration of the M16 was not available during the period Norcos took place. In one seen in fact an M4 has an EOTech optic mounted on it...backwards. Not only is the optic backwards, EOTech was not founded until the late 90's or early 2000's.
Factual error: The real RAF chief meteorologist was Group Captain Stagg. For some reason, he is the only character in the series who has been fictionalised, as Captain Burns. However Captain is not an RAF rank. Unlike the fictional Burns, Stagg was not a pilot and had no medal ribbons (he had no previous military service before receiving a war commission for his meteorological skills).
Factual error: Almost none of the senior police officers wear the correct medal ribbons. Brian Moore and Pat Geenty wear the Order of the British Empire, which neither had. Geenty wears the General Service Medal, for military service in Northern Ireland, although he was never in the armed forces. Moore does not wear the Queen's Police Medal, which he was awarded in 2009. Both wear the Diamond Jubilee Medal in 2011, although it was not awarded until 2012. Andy Parker wears an unidentified ribbon (possibly intended to be the Queen's Police Medal, which he was awarded in 2010, but looking nothing like it) and the Golden Jubilee Medal, but does not wear the Diamond Jubilee Medal or the Police Long Service and Good Conduct Medal to which he was also entitled. Mike Veale and Ray Hayward wear no medal ribbons at all, although both would be entitled to the Golden Jubilee Medal and Police Long Service and Good Conduct Medal (and Veale also to the Diamond Jubilee Medal after 2012).