[1] Smith was elected as a Democrat to the United States House of Representatives, serving as a United States representative from Connecticut from 1935 to 1941 (in the Seventy-fourth, Seventy-fifth, Seventy-sixth, and Seventy-seventh Congresses).

He resigned from Congress on November 4, 1941, to accept appointment to the federal bench.

[1][2] Smith was nominated by President Franklin D. Roosevelt on October 16, 1941, to a seat on the United States District Court for the District of Connecticut vacated by Judge Edwin Stark Thomas.

His service terminated on September 13, 1960, due to his elevation to the Second Circuit.

[1] Smith was nominated by President Dwight D. Eisenhower on January 11, 1960, to a seat on the United States Court of Appeals for the Second Circuit vacated by Judge Carroll C. Hincks.