Municipal Police established in NYC

The New York City Police Department (NYPD) was officially established in 1845 to replace the ineffective night watch system. It was modeled after London's Metropolitan Police, adopting a military-style structure. Initially, New York City had only a small force of constables, marshals, and municipal officers. The 1844 Municipal Police Act authorized a 1,200-officer force, but disputes delayed its implementation. The city was divided into districts with courts and station houses, and in 1853, the department introduced its signature navy blue uniform.

In 1857, the Municipal Police were replaced by the State-controlled Metropolitan Police, consolidating forces across New York City and surrounding areas. Mayor Fernando Wood resisted, leading to months of chaos with two rival police forces. Clashes erupted between them, culminating in a violent brawl at City Hall. The State's Court of Appeals ruled in favor of the Metropolitans, forcing Wood to disband the Municipals. However, the inexperienced Metropolitans struggled to maintain order, leading to riots on July 4 and further unrest in Little Germany.