While he was a law student at Yale University, he participated in the Freedom Ride from Atlanta, Georgia, to Montgomery, Alabama.
In 1961, William Sloane Coffin invited second-year law student Smith to go to Montgomery, Alabama, as a Freedom Rider.
He then spent a decade as law secretary to New York State Supreme Court Justices Jawn A. Sandifer, Edward R. Dudley, and Harold A. Stevens.
Smith's best-known opinion for the Court was People v. LaValle, a 4-to-3 decision holding that New York's death penalty statute was unconstitutional due to the structure of its sentencing procedures.
[6] After leaving the bench, Smith became a partner at the New York City law firm of Chadbourne & Parke and also worked as a mediator at JAMS.