He, along with William "Big Bill" Devery and Thomas F. Byrnes, were among several senior NYPD officials implicated by the Lexow Committee during the 1890s.

[1][2] His first post was at the 47th Precinct in Brooklyn where he remained until 1868 when he was transferred to Broadway, then a dangerous and high-crime area, commonly known as "a district infested with crooks and thugs of all description".

He was made a roundsman on July 10, 1871, and then appointed to sergeant on September 23 whereupon he was assigned to lead the then newly formed "mounted squad".

He spent the next three years in other poor high-crime areas using his aggressive "rough-and-ready" policing methods until September 30, 1876, when he was transferred to the West 13th Street Station.

[1] The precinct was one of the most important posts in the city, being the center of the Broadway's night clubs, gambling resorts and "disorderly houses".

Referring to the increased amount of bribes he would receive for police protection of both legitimate and illegitimate businesses there – especially the many brothels – Williams said, "I've been having chuck steak ever since I've been on the force, and now I'm going to have a bit of tenderloin.

[2] He remained in the Tenderloin for two years, Max F. Schmittberger and James K. Price both serving as his wardmen, and was briefly detailed as Superintendent of Street Cleaning until his return on June 15, 1881.

[1][2] In response to frequent criticism of excessive force, Williams once said "There is more law in the end of a policeman's nightstick than in a decision of the Supreme Court".

He claimed that he had acted against some "disorderly houses", but was unable to recall the names or addresses, while he had allowed others to continue operating because they were "fashionable".