The New York City Police Department (NYPD) , the largest police department in the United States, has primary responsibility for law enforcement and investigation within the five boroughs of New York City. It is considered to be the first "modern" style police department in the United States; when it was created in the 19th century, it was modeled after London's Metropolitan Police.
The New York City Transit Police and Housing Police were fully integrated into the NYPD in 1995; some new police officers are randomly assigned to the Transit and Housing units.
The Compstat program, introduced under then-Commissioner Bill Bratton in the 1990s, uses statistics about crime rates and arrests to evaluate police precincts and commands. As of June 2003, there are charges that some precinct commanders have been falsifying crime reports and other data to make the statistics for their areas look better.
The size of the force has fluctuated, depending on crime rates, politics, and available funding. In June 2004, there were about 40,000 sworn officers plus several thousand support staff.
The NYPD is headed by the New York City Police Commissioner with the senior sworn officer being titled the Chief of Department. It is divided into 10 bureaus. Each is headed by a Bureau Chief, with the Detective Bureau being headed by the Chief of Detectives.
The NYPD Highway Patrol -- also known as the New York City Police Department Patrol Services Bureau or NYPD Highway District -- is a specialized unit under the auspices of the NYPD's Transportation Bureau primarily responsible for patrolling and maintaining traffic safety on limited-access highways within New York City.
The NYPD Highway Patrol's origins begin in 1911 with the formation of the NYPD's first motorcycle squad, which was formed to meet the challenges of handling increasing traffic danger concomitant with the rise of automobile use.
The NYPD Highway Patrol is currently divided into five command units which correspond with the five boroughs of the city -- Highway Unit #1 in the Bronx, Highway Unit #2 in Brooklyn, Highway Unit #3 in Queens, Highway Unit #4 in Manhattan, and Highway Unit #5 in Staten Island.