Lindley Garrison Beckworth, Sr., United States representative, judge, and lawyer, was born on June 30, 1913, in Kaufman County, Texas, to Otis Jefferson and Josie (Slaughter) Beckworth. He attended several common schools in Upshur County and in 1928 enrolled in Gilmer High School, from which he graduated in 1931. Like both of his parents, Beckworth became a teacher. After attending Southern Methodist University in 1931–32, he taught at Shady Grove in Upshur County during 1932–33. He attended Sam Houston State Teachers College (now Sam Houston State University) the first summer term of 1933 and the University of Texas from July 1933 to June 1934. In the spring of 1934 he worked for the Civil Works Corps and took correspondence courses from Abilene Christian College. He taught during the 1934–35 and 1935–36 school years, attended the University of Texas law school during the summer of 1935, and attended Baylor University law school in the summer of 1936.
In January 1936 Beckworth, a Democrat, announced his candidacy for the state legislature. He later defeated five candidates in the first primary, but did not receive a majority of the votes. In the runoff he was nominated by a 3,343-vote margin. After representing the Fourth District in the Texas House of Representatives for one term, he was one of five candidates who ran against incumbent Morgan G. Sanders in 1938 for the Third Congressional District seat. With his father as campaign manager, Beckworth led in the first primary. He defeated Brady Gentry in the second primary and went on to become, at twenty-five, the youngest person elected to the United States House of Representatives in the twentieth century. He served seven terms in the House and in 1952 announced his candidacy for the Senate seat that Thomas T. Connally was vacating. Despite a three-month, 20,000-mile campaign, Beckworth lost to Price Daniel, Sr., by a three-to-one margin. After losing the 1954 election for his old House seat by less than 1,000 votes, he recaptured it in 1956. In the United States House of Representatives Beckworth was an advocate of small farmers and businessmen, servicemen and veterans, and education. His House committee memberships included Interstate and Foreign Commerce, Post Office and Civil Service, and Foreign Affairs. He was the chairman of the Texas congressional delegation in 1952.
The 1965 Reapportionment of Congressional Districts Act eliminated Beckworth's district and placed him in the Fourth Congressional District, represented by Ray Roberts. He lost to Roberts in the 1966 primary. President Lyndon B. Johnson appointed him to the United States Customs Court on March 14, 1967, and he served until August 1968. He then practiced law in Longview with the firm of Whitehead and Whitehead. In November 1970 he was elected to the Texas Senate from the Second Senatorial District. As a state senator, he worked for the establishment of the University of Texas at Tyler and the University of Texas Health Center at Tyler. He served one term and returned to his law practice.
Beckworth married Eloise Carter of Tyler on June 27, 1942; they had two daughters and three sons. Two of the sons subsequently practiced law with their father. During and after his congressional career, Beckworth lived in Upshur County. He was admitted to the State Bar of Texas in 1937, was a member of the Forum Law Society, the Masons, and the Odd Fellows. He was a Baptist. He died on March 9, 1984, at the University of Texas Health Center in Tyler and is buried in Rose Hill Cemetery, Tyler.