With his slicked-back hair, Queens accent and entourage of mostly white, male union lieutenants, Patrick J. Lynch moves through New York as the rough-around-the-edges, unapologetic labor leader for more than 22,000 street officers.

His public persona — greeting officers on the street and delivering speeches with a cadence that reaches for the Kennedyesque — ranks him among the most recognizable police officers in the city.

But behind the raffish facade is a shrewd tactician who, according to his allies and those who have faced off against him, has proved adept at negotiating deals when it fits his interests, and tangling with mayoral administrations, Democrat and Republican alike, when it has not. It has kept him at the helm of the Patrolmen’s Benevolent Association for 15 years, representing the bulk of the nation’s largest police force even as it bears less and less resemblance to his Irish Catholic roots.

His latest battle, though, far eclipses anything before.

Amid the furious national debate over race and policing, his pugilistic defense of police officers and his vitriolic critiques of Mayor Bill de Blasio have been seen across the country in the days since two police officers were killed in Brooklyn.