Born in Seattle, Washington, in 1904, Carl McFarland received his B.A. (1928), his M.A. (1929), and his LL.B. (1930) from the University of Montana. In 1932 he earned an S.J.D. from Harvard Law School, and a year later his dissertation, Judicial Control of the Federal Trade Commission and Interstate Commerce Commission, was published. Returning to Montana in the fall of 1932, McFarland joined the law firm of Toomey and McFarland in Helena. Early in 1933 he accepted the Montana State Supreme Court's offer to act as Commissioner of the codification of the Montana statutes. He had barely begun this work when he left to join the Department of Justice in Washington. First employed as a special assistant anti-trust attorney, McFarland was later appointed assistant attorney general. In charge of the vast Lands Division, he was instrumental in drafting much New Deal legislation. Also during this period McFarland co-wrote Federal Justice with Attorney General Homer S. Cummings. He received the American Bar Association’s first Ross Award in 1934.

By 1939 both men had left the Justice Department. McFarland joined Cummings in private practice at the latter's Washington firm of Cummings and Stanley (later called McFarland and Sellers). Beginning in 1940 McFarland was active in American Bar Association committees, chiefly the Legislation and Administrative Law Committee. In this capacity he was the principal draftsman of the Administrative Procedure Act, the federal statute which provides for the governing of more than one hundred governmental agencies and which was voted into law in 1946 without a single dissent in either house. For his contributions to this legislative achievement, McFarland was awarded the American Bar Association's Gold Medallion. Following the passage of the bill, he served a brief term as Chairman of the Civil Service Commission's Hearing Examiner Board in 1948-1949. Leaving private practice in 1951, McFarland began an eight-year stint as president of the University of Montana. He joined the faculty of the University of Virginia Law School in 1959. His courses included Administrative Law and Legislation. An authority on legislative and administrative law, McFarland served on the Hoover Commission, the President's Conference on Administrative Procedure in 1954-1955, and the Virginia Code Commission. He was consultant to the Virginia Commission on Constitutional Revision and chairman of the 1968 United States Public Land Law Revision Commission. He died in 1979.