Dallas police said an officer was injured Monday when a bullet fired at him hit the microphone on his lapel.
The officer was responding to a report of a man randomly firing at a far North Dallas apartment complex at about 5:30 p.m.
"Seeing his microphone and where we wear them on our shoulders, he is ... extremely lucky," Senior Cpl. Kevin Janse said. "We're talking a matter of centimeters, and this could have been a whole different story."
Police said the bullet shattered the microphone and lodged in the officer's jaw.
Dallas police have not released the name of the officer, who is in his late 60s.
Police Chief David Brown said the officer is doing "remarkably well."
Police said 19-year-old Bryson Howard was roaming the Village of Timberglen complex in the 3500 block of Timberglen Road with a loaded revolver. Howard had been arguing with his aunt, police said.
Howard opened fire on the officer before he could get out of his squad car, police said.
"It came through the window, hit his lapel mic and went into his neck, so the lapel mic more than likely saved his life," Janse said.
Howard then turned the gun on himself and died at the scene, investigators said.
NBC 5's Ellen Goldberg contributed to this report.