- Contents Justices Guides Case List Introduction Thurgood Marshall (1908-1993) Solicitor General of the United States, appointed by Lyndon Johnson (D) in 1967, served until 1991. Replaced Tom C. Clark, succeeded by Clarence Thomas. Marshall became a predictable ally of the remaining libertarian activists on the Court. His career has been somewhat uneven participatorily. It has reached high points ...www.ripon.edu/faculty/bowenj/antitrust/Marshall.htm