Revelations - S3-E6
Continuity mistake: When Tim puts Lucy in the squad car after "arresting" her, the rear door on the driver side is open, but when the camera pans back to her it's suddenly closed without making a sound.
Continuity mistake: In the episodes before "La Fiera," Nolan's new truck is a black Toyota Tundra. However, after that episode, it changes to a Nissan Titan, yet his character still says, "black Toyota Tundra."
Revelations - S3-E6
Continuity mistake: When Nolan is asking for advice from his ethics teacher, she says, "It's 2021." However, with the 2019 start time for the rookies and a supposed year's probation, this shouldn't be possible from the show's timeline perspective.
Training Day - S6-E4
Continuity mistake: When Tim and Aaron are questioning a suspect, Aaron comes out of the room to talk to Tim and shuts the door behind him. When it cuts back to Aaron, the door is open. (00:09:16)
Continuity mistake: Austin and Tamara are standing and picking out snacks at the attorney's office. Lucy walks up, and Austin and Tamara turn around. His hands are by his side. When the camera angle changes, his hands are in his pocket. (00:18:29)
Continuity mistake: When Angela is eating a pickle with Marshmallow fluff, there is only one more bite of pickle left. However, when the camera turns, she has a whole pickle again. (00:05:15)
Answer: Window tool.