By ordinance of May 13, 1836 the force of the First Municipality Guard was set at one captain, one lieutenant, two sergeants, forty privates, and ten lamplighters. This force apparently operated according to existing ordinances until the passage of new legislation officially organizing the Guard on February 24, 1837. That law increased the size of the force and provided that it be composed of men "in good condition to serve, intelligent, and speaking French and English." These men were to be controlled by the captain, but were always at the orders of the Mayor, Recorder, and Aldermen. The force was divided among posts at the City Hall, in the Faubourg Treme, and at Bayou St. John. Its officers were appointed by the Mayor, with Council consent; the other members were named by the captain, with the consent of the Mayor. All were required to give security to assure the faithful performance of duties and to swear to enforce the laws of the Municipality.

By ordinance of July 27, 1840 the Guard was reorganized (the legislation referred to the body as the Department of Police) into a night watch and a day police. Both branches were under the command of the captain, who held the title "high constable" in connection with his day police duties. The captain was to keep a record of the officers and men under his command and was also to maintain a general record of all police activities. The lieutenant at the post of the Faubourg Treme was also to submit daily reports of activities to the captain.

The night watch was to assemble at sunset and remain on duty until daylight; the men were also to report for duty during the day when called out by the Mayor or Recorder. They were to arrest slaves out at night without passes; to arrest suspicious persons; to report on the lamps; to order the closing of cabarets "after gunfire;" to arrest offenders causing any breach of the peace; and to sound the alarm for fires. An armory of muskets and swords at each watch house was to be used only when conditions warranted, as determined by the Mayor or other responsible officer.

The day police was composed of a number of privates who formed a corps of constables. They were to perform such duties as were required by their superiors and were also to attend to fires occurring at night. The high constable was to report daily to the Mayor and Recorder on matters relating to the police and was also to keep a register of the arrival of strangers under suspicious circumstances. He was assisted by the lieutenants of the watch.