Elected as a Democrat to the Seventy-third and the two succeeding Congresses, Beiter was U. S. Representative for the forty-first district of New York from March 4, 1933, to January 3, 1939; and was chairman of the Committee on War Claims during the Seventy-fifth Congress. An unsuccessful candidate for reelection in 1938 to the Seventy-sixth Congress, he was assistant to the United States Secretary of the Interior in 1939 and 1940. He was then elected to the Seventy-seventh Congress and served from January 3, 1941, to January 3, 1943, but was an unsuccessful candidate for reelection in 1942 to the Seventy-eighth Congress.