Benet was born in Abbeville, South Carolina on December 26, 1879; he attended the common schools in his youth, and matriculated at the College of Charleston, the University of South Carolina, and the University of Virginia. He studied the law, and upon his admission to the bar began practice in Columbia, South Carolina, in 1903. Solicitor of the fifth judicial circuit in 1908, Benet became Columbia's city attorney from 1910 to 1912. He was the secretary of the Democratic State committee three times; on July 6, 1918 he was appointed to the Senate to fill out the term of Benjamin R. Tillman, who died in office. He served unil November 5, when a successor to the position was elected; Benet himself was an unsuccessful candidate in the same election to fill the vacancy. During his brief time in the Senate, Benet was the chairman of the Committee on National Banks; upon his defeat, he resumed his practice. From 1915 he was a member of the board of regents of the South Carolina State Hospital, later becoming the chairman of the board; in this capacity he served until 1946. During World War II Benet chaired the War Finance Committee for South Carolina, and was serving as the chairman of the Alien Enemy Hearing Board for the state's eastern district at his death; he died in Columbia on March 30, 1951, and was interred locally in Elmwood Cemetery.