Other mistake: Kim and Al chase the suspect into a wooded area. As Al is walking through the woods there is a puff of smoke from behind the the trees in front of him, but the suspect steps out from behind him.
Chicago P.D. (2014)
1 other mistake in season 4 - chronological order
Starring: Sophia Bush, Jason Beghe, Patrick John Flueger, Jesse Lee Soffer
Character mistake: When Ruzek and Voight are questioning Wade Henslow (the father of missing girl) at the station, after finding out he lied and set up his own security to find his daughter Adam looks at Wade Henson but addresses him as "Mr. Larson" which is actually the last name of one of the kidnappers they found DOA who got into the gun fight with his security guy, the ex-cop Kenny. (00:21:26)
Question: Atwater is always going undercover as a drug dealer; after all these years, how does he get away with not being recognised?