It was fitting that Taft—a lover of the judicial branch and a future Chief Justice of the U.S. Supreme Court—had more appointments to the U.S. Supreme Court than any other single-term president in history. He appointed five men as associate justices: Horace H. Lurton, Charles Evan Hughes, Willis Van Devanter, Joseph R. Lamar, and Mahlon Pitney. He also elevated sitting associate justice Edward D. White from associate justice to chief justice.

Lurton served on the Court from 1910 until 1914. Taft had served with him on the 6th U.S. Circuit Court of Appeals. Hughes, the governor of New York, served on the Court as an associate justice from 1910 to 1916. He left the bench to run for president. He captured the Republican nomination, but lost a close election to incumbent Woodrow Wilson. Devanter served on the court more than twenty-five years from 1911 to 1937. He served with Chief Justice Taft, the man who had appointed him. Lamar served five years on the Court from 1911 to 1916. Pitney served ten years on the Court from 1912 to 1922. Taft elevated Edward D. White from associate justice to chief justice in 1910. White served as chief justice until his death in 1921. Taft succeeded White as chief justice.