It happened around 1 a.m. Saturday at D Street and Allegheny Avenue.
According to authorities, the 24th District sergeant was traveling east on Allegheny when another driver traveling west crossed the center line.
The driver struck the sergeant's vehicle.
The sergeant was taken to the hospital with a leg injury.
The driver of the striking vehicle is in critical condition with multiple injuries.
He faces charges of Driving While Intoxicated.
Police said a syringe was also found in his car.