Color of the day (police)

The color of the day is a signal used by plain clothes officers of some police departments in the United States. It is used to assist in the identification of plainclothes police officers by uniformed officers. Perhaps its best known use is by the New York City Police Department (NYPD), the NYPD Transit Bureau (formerly the New York City Transit Police) and the NYPD Housing Bureau (formerly the New York City Housing Authority Police Department) among other law enforcement agencies.

A "plain clothes" police officer will wear a headband, wristband or other piece of clothing in the "color of the day"; and officers will be told of this color at the police station before they start work. The system is for officer safety and first started during the violence of the 1970s and 1980s in New York City.

New York City is a city with a population of over 8,310,000, with over 18,800,000 people living in the surrounding area. An extra 500,000 people enter the city during a weekday.

The color of the day system is about officer safety. With so many armed officers in the city, undercover police officers need to have an easy-to-use system to provide for discreet identification of plainclothes officers by uniformed ones. The system is in place to prevent friendly-fire incidents from uniformed officers from mistakenly shooting plain-clothed officers not immediately identifiable as police officers.

The now-defunct NYPD Street Crime Unit started in 1971. From the late 1970s through the early 1990s, crime in New York City was at record levels. Undercover officers were asked to go into the New York City Subway and other such high-risk areas in plain-clothes or dressed as a homeless person as a decoy. Many of these officers feared that uniformed officers would mistake them for criminals in a use-of-force situation.

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