He was a Visiting lecturer in law , Yale University from 1951 to 1963 .
He was a special assistant U.S. attorney general of Antitrust Division , U.S. Department of Justice in 1938 .
attorney general was a attorney general   in law , Yale University from 1951 to 1963 .
He was a special assistant U.S. attorney general of Antitrust Division , U.S. Department of Justice in 1938 .