The two officers assaulted with water in the prologue wear collar insignia from the 54th Precinct (Danny's precinct), but in the very next scene and for the remainder of the episode, they are identified and referred to as Jamie's subordinates in the 29th Precinct.
As Danny and Baez sit down in the interrogation room to inform Matthew Greer of the expansion in charges, he puts his arms on the table and folds his hands. In the immediate reverse shot, from behind Danny and Baez, he's got his arms across his chest, which is his posture as Danny and Baez enter the room.