"Hey, listen to me, Batwoman. I like how you start getting suspicious the moment you see people laughing—it makes us all feel so safe. But Gotham was practically hell on earth in the first half of the year. You have to give people a chance to find joy in suffering. Unless you actually see Joker spreading laughing gas, let people relax for one night."
Barbara tried to reason with Batwoman while quickly scratching at the dried cola stains on the keyboard with her fingernails.
Earlier, when Batwoman arrived at the police station, she had given Barbara a task. While she went to the Hall of Justice to meet Deathstroke, Barbara had already begun secretly investigating the police station shooting.
The method was simple: gunshot detectors.
In the United States, many cities with poor public safety had similar equipment, such as Detroit, Star City, and Gotham.
These small devices were essentially microphones mounted on Telephone Poles or streetlights. When they detected a specific sharp noise within range that exceeded a certain decibel level—gunshots, cannon fire, explosions, and the like—multiple devices automatically used triangulation to pinpoint the source and simultaneously sent the coordinates to police records.
Gotham's only problem was that gunshots were too frequent. Whenever Nightfall descended, gunfire throughout the city sounded like someone frying beans, crackling endlessly from every dark corner.
To identify the assassin's weapon and firing position under such circumstances required a highly experienced old Gothamite, someone who could sift through countless alarms from the same time period and isolate the most suspicious shot.
Barbara had done it. After locating the gunfire, she went out herself, beat up several gang members, bribed several homeless people, and obtained an extremely blurry phone photo.
An old homeless man had taken it secretly from beneath some cardboard with a cheap phone