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.
This Is Your Brian on Drugs - S1-E11
Factual error: After Agent Rooks has taken NZT he does Sudoku puzzles. When Brian is flipping through the puzzles, the first 2 pages seem OK, but after that, the rest of the puzzles are filled in wrong, not a mistake someone on NZT would do.
Undercover! - S1-E15
Factual error: When in the search for Lucy Church, Brian says he is looking for a blue 1968 Ford Mustang. The mustang in the episode is either a 69 or 70 coupe. (00:05:30)