Sooner or later, if you are out there bangin', either your gang or another gang will do you in," says Jim Mullen, speaking to 300 high schoolers on Chicago's Northwest Side. "If you are out in the street, something's going to happen."

Mullen, 33, knows. In October 1996, he and fellow patrolmen from the Rogers Park police district surrounded an apartment building after neighbors reported shots being fired at a passing elevated train. According to police reports, George J. Guirsch, 61, an off-duty security guard, emerged from the building carrying a pistol. In an ensuing scuffle, a bullet that police say was fired from Guirsch's .357-magnum pierced Mullen's right cheek, shattered his jaw and ripped into his spine at the base of his skull, permanently paralyzing him from the neck down. (Guirsch was charged with attempted first-degree murder and is currently in Cook County jail awaiting trial.) "Once I had a promising future, with a wife and baby," Mullen says. "Now my life was over as I knew it."

But after four operations and 57 days in intensive care, Mullen, the son of John Mullen, a retired Chicago police sergeant, and his wife, Audre, a retired secretary, found a new reason to live. As a quadriplegic on medical disability, he was entitled to his $42,000 salary for one year, followed by 10 years at a 25 percent reduction and half salary after that. Instead, Mullen asked to remain on the job—and to keep his uniform.

Today Mullen works as an outreach coordinator for the city's community policing program, a position that pays $60,000 a year and combines desk work with speaking engagements at schools, churches and community centers. And since serving as grand marshall of Chicago's St. Patrick's Day parade last March and receiving a visit from Hillary Rodham Clinton in October, he has become something of a local celebrity. "He's going to lift up the visibility of our program," says his supervisor Ted O'Keefe. "People in the community have rallied around him."

No wonder. Despite his reliance on a ventilator and 24-hour nursing care, the always smiling Mullen exudes a rare personal charm. Now, thanks to a one-story house equipped with voice-activated lights and doors, where he lives with his wife, Athena, 35, a police officer assigned to the same district, and their daughter Maggie, 21 months, he can act on the same advice he gives kids in tough neighborhoods. "This is the hand I was dealt," he says, "and I just have to play it."