[1] He was born on February 18, 1919, in Manhattan, New York City,[2] the son of immigrants from Saint Kitts.
He dropped out of Morris Evening High School, and worked as a clerk for the New York City Rent Commission.
Warner was elected on January 14, 1958, to the New York State Assembly (Bronx Co., 6th D.), to fill the vacancy caused by the appointment of Walter H. Gladwin as a City Magistrate.
He was re-elected in November 1958, and remained in the Assembly until 1960, sitting in the 171st and 172nd New York State Legislatures.
In September 1965, he ran in the Democratic primary for Borough President of the Bronx, but was defeated by Herman Badillo.