The origin of the Trenton Police Department can be traced back to December 29, 1792, when the city created the position of town Marshal. John Potts was the first Marshal of Trenton and part of his duties required him to walk through all parts of the city, at least once a week, enforce city ordinances and to watch for fires.
During the early years of the department the primary concern of the residents was the danger of fire. Volunteers were used as night-watchmen to augment the service of the Marshals. Eventually, each ward of the city employed a night-watchman who answered to the Marshal. The duties of the Marshal and watchmen expanded through the years and, after many changes, evolved into the current police department.
A more detailed history of the department can be found at the Trenton Police History Project. Written and visual histories of the department are presents along with numerous digital copies/transcriptions of primary documents.
Progress depends on retentiveness.
When experience is not retained infancy is perpetual.
Those who cannot remember the past are condemned to repeat it. -- George Santayana, philosopher