Ethan Garvin is an analyst who works in the NYPD’s Real Time Crime Center. He handles a program called ShotSeeker, which uses audio surveillance systems around the city to locate gunshots. It’s his job to double check if the gunshots are real or false alarms. This subtle plot point — that Garvin is responsible to varying ShotSeeker’s results — highlights how even the most sophisticated technology requires a human hand to keep an eye on it.