The Highway Patrol are specialized units part of the Highway District with the Transportation Bureau of the New York City Police Department. The Highway Patrol is primarily responsible for patrolling and maintaining traffic safety on limited-access highways within New York City. The Highway Patrol's other duties and roles include accident investigations, advanced driver and radar/laser speed enforcement training for NYPD officers, field sobriety testing at the various testing locations in each Patrol Borough, dignitary and parade escorts, hazardous material and truck traffic enforcement, anti-drag racing programs, and anti-terrorist checkpoints at key bridges and intersections in the city.