NEW YORK (PIX11) — Though police in New York City are committed to using the latest technology to fight crime, a feature at the front doors of NYPD precincts dates back centuries. 

Visitors to precincts may notice lights covered in green glass outside. Their use dates back to the 1650s, before New York City was New York City, police explained. The Rattlewatch, the first police force in the area, was developed in 1651, former NYPD Commissioner Ray Kelly wrote in a 1993 paper about the history of the NYPD.

A green light is shown outside the NYPD 17th Precinct building in Manhattan on Jan. 4, 2023. (Aliza Chasan/PIX11)

“It was a voluntary patrol composed of citizens appointed by the council. In addition to muskets, its members were equipped with the hand rattles that gave the fledgling police force its name,” Kelly wrote. “They strolled the streets to discourage crime and search for lawbreakers. In times of emergency, they noisily spun their rattles to summon assistance from fellow Rattlewatch members.”

The green lights also go back to the start of the police department, Darrin Porcher, a former NYPD lieutenant, explained. It’s believed the Rattlewatch members carried lanterns with green glass as a means of identification, police said. The Rattlewatch members would hang the lanterns on hooks by the front doors of watch houses to let people know a watchman was there and available. 

“They were not 24 hour facilities,” Porcher said. “When the green light was on, that was an indicator to the public that they were available for service.”

Police continue to flank their entrance doors with green lights. 

“The green lights that hang outside the entrances of police precincts are a symbol that the ‘watch’ is present and vigilant,” NYPD Bronx tweeted back in 2020.