Goofs

The uniform that Sgt Grey is shown wearing, supposedly from his "rookie' year with the LAPD is not in fact an LAPD uniform. It appears to be that of a Sgt in the NYPD (including precinct assignment insignia). It is a still from the actor's role in Phone Booth (2002)

When Chen and Bradford go to arrest Rowan Clausen, Chen says they are arresting him for the murders of Patrick Hayes and Morris Mackey, However, they can't arrest him for Patrick Hayes' murder because he was murdered in France, not the U.S., so they wouldn't have jurisdiction to arrest Rowan for that crime. They would have to send him back to France for that.

In the part where Aaron is with Patrick from their early years partying and he throws him in the pool. They are portrayed by the current day actors. Then later when the past is shown where Aaron discovers the dead body, chronologically this would have been after their party days but they are portrayed by other actors who are shown as younger.

The footage of Aaron throwing Patrick in the pool was real footage whereas the scene showing him finding the body was a reconstruction. Hence the different actors.

During an interview Lopez cracks a joke that she'd like to stab Wesley sometimes over dirty dishes. Character wise it would make more sense for this line to come from Wesley, as in S2E01 Lopez is revealed to be a major slob; dirty clothes everywhere, plates left lying around, even a grilled cheese sandwich left in the shower overnight.