A police tracer is a device used by the police to track down whoever pressed the tracer's button. The appearance of the device is a simple one, only comprising of a big red button and another part that either acts as a speaker or microphone for one-way transmission. Pressing the button will allow the police to locate the source of trouble and arrive in force to assist the presser. Officer Murphy gave one of these to Blaze Fielding in the Streets of Rage story at City Hospital, insisting that he couldn't quit the force to join them due to his wife and child. Blaze took this device to several places before locating the kidnapped Max Hatchet at Hawk's foundry. Before she could press the red button, Blaze was captured and the tracer was thrown away by Hawk (oddly, although one crook worried it was a bomb, Hawk was an ex-cop and recognised it but did not destroy it). Seeing the help it would give, Max broke away from his captor and activated the tracer, alerting Murphy and Axel Stone to their presence.
The tracer is somewhat taken from the first Streets of Rage video game, where pressing the A/special button with a sufficient power-up in storage would call a police car from off-screen to fire in heavy artillery, much like the incendiary bomb in the comic. This would be replaced in the next game by reusable special moves that cost health, completely eradicating any references to the police.