Factual error: When discussing a recent search of a suspect's home, Hill Harper says "we got his hard drives", but pulls a computer power supply out of a bag. Hard drives are significantly smaller and don't have a bundle of wires coming out the back of them.
Factual error: There is a periodic table shown in the background of the lab, showing an accurate periodic table as of now. During 1945, at least 21 elements had not been discovered. (00:17:40)
Us vs. Them - S2-E2
Factual error: We see Liam's driver's license. It says he's from Rhode Island, but the license looks nothing like RI's. It's issued by the State Motor Vehicle Commission, but RI does not have an MVC (only New Jersey does). And the expiration date is always the same as the holder's birthday, but here we see it's 2 days after his birthday.
Factual error: The Marine Colonel in Supergirl played by Eddie McClintock spends all of his time wearing Marine Officer's Dress Blue Bravos. Marine Dress Blues are ceremonial uniforms. On rare occasions, the Charlies or Deltas (no coat) may be worn as a work uniforms (the primary exception to this rareness being recruiters). The full uniform is certainly not worn for day to day work in the field.
Factual error: At an eating area, a collector shows a man a computer screen with his daughter in real time and has her call him. She then speaks in the phone and you can see her lips and actions lining up perfectly with the words he is hearing. It would not be this perfectly in sink even in the most optimal of conditions. There is a slight delay between the video from the camera and sending that to the computer being shown. And then there is also a slight delay of the phone single traveling through one phone to the other. These would not line up right and so the father would not see the lips moving exactly with what he hears his daughter saying over the phone.
Factual error: As Ren enters Renautas and meets Emily, the word "Welcome" keeps scrolling in various languages on the screens in the background. Although hardly seen, the Hebrew is wrong, as it is reversed (text from left-to-right, as opposed to right-to-left).
Factual error: In the transition shot showing Hobart Building in San Fransisco, items not belonging to the scene are visible and have not been edited out. These items include; modern phone numbers, web addresses for several companies and educational institutions, satellite dishes and American flags. (00:24:10)