Police deputy Tony Brown was an officer in the Boston State Police Department. Brown first met undercover cop Billy COstigan in the Boston police uni before ranking into a police deputy. After the university days, Brown became an officer in the Boston PD working under the unit of Captain Oliver Queenan.
The meeting at 344 WashEdit
After Costigan gained the evidence on Sullivan being Costello's mole, he ordered a meeting with him at the rooftop of 344 Wash, down K street. Having his initial plan be to arrest Sullivan, he contacted the only two police officers he trusted to come along. Srg. Dignam and deputy Brown. Costigan told Brown to bring Dignam, but for unknown reasons he did not.After confronting each other, Costigan leaves the rooftop with Sullivan, only to get shot in the head by Barrigan, who also was a mole of Costello's. Brown quickly came downstairs, only to find Costigan's body on the floor, and seconds later, shot dead by Barrigan.