Chin Check - S1-E3
Factual error: The cops raid a house and find some rifle ammunition. The female cop says "cop killers." A few seconds later three cops are looking at the bullet and a box used to store it, it appears to be a 5.56x45mm round used in the AR-15 style rifles. All high powered rifle ammunition, doesn't matter if its bullet is fmj or armor piercing will go through soft armor which is what all police officers wear. Such ammo is available to civilians in every store. All rifle ammo could be considered "cop killer." (00:03:50 - 00:04:56)
Factual error: Peggy and Ed are hiding out in a cabin "just outside of Sioux Falls," but are somehow also close to Mt. Rushmore. Mt. Rushmore is near the western border of SD, Sioux Falls on the eastern border, more than 340 miles apart.
Factual error: LaSalle's 2015 pickup truck is shown with a green Louisiana license plate. Those plates were only distributed in 2011 and 2012 in celebration of Louisiana's Statehood bicentennial. Furthermore, pick-up trucks in Louisiana are always provided with basic seven digit plates with only the state name, the digits, and the state motto Sportsman's Paradise. The vehicle owner could request a vanity plate with a specific order of digits, or a sport's design, but again, the state hood could not be one.
Factual error: The address on Lee's business card shows her zip code for Atlanta, GA as "11453." This is a non-existent US zip code, and the zip code for Atlanta is "303xx."
The Legend of Curtis Ballard - S2-E3
Factual error: In the first flashback scene of Ballard serving a Mormon mission in Lithuania, he laments that he has been on his mission for 18 months and has yet to baptize a single person. In a later flashback scene when he and his companion are visiting the prostitutes, he states that he and his companion are 19 years old and they should be in college, going to parties, getting drunk, getting laid, etc. Instead of serving missions. These scenes take place in 1991, at which time young men did not serve missions for the Mormon church until after they turned 19, so if Ballard had already been on his mission for 18 months, then he should have been at least 20 years old, and closely approaching 21.
Factual error: When the two officers salute in Iraq, they give a naval (or American) style palm-down salute, not a British Army palm-forward salute.
Episode #1.5 - S1-E5
Factual error: Catherine is told she's been recommended for the Queen's Police Medal for Gallantry. This has not been awarded since 1977, when it was replaced by the Queen's Gallantry Medal, which is still awarded.
Factual error: Congressman Tate and his brother are on the shooting range. They are wearing high-tech electronic earmuffs that block harmful noise like gunfire while amplifying speech and other low-volume sounds. Although, they are wearing high-tech earmuffs, they both have an ear exposed so they can hear each other talk. (00:13:00)
Factual error: A number of times throughout the season they refer to LSD being found in dead bodies and LSD being matched with other LSD found in other (living or dead) bodies. LSD starts a chain reaction in the brain which requires about an hour to take a noticeable effect. And, by that time, it has completely broken down and no longer exists as LSD in the body - before the person even begins to get high. There is no test for LSD even in the most bombed living individual, let alone a dead body years later.