Born on August 12, 1912, in
Elmira,
New York, MacMahon received an
Artium Baccalaureus degree in 1936 from
Cornell University and a
Bachelor of Laws in 1938 from
Cornell Law School. He was a lieutenant in the
United States Naval Reserve during
World War II from 1944 to 1945. He was in private practice in
New York City from 1942 to 1953 and again from 1955 to 1959. He was the Chief
Assistant United States Attorney for the Southern District of New York from 1953 to 1955. He was the
United States Attorney for the Southern District of New York in 1955.
Federal judicial service MacMahon was nominated by President
Dwight D. Eisenhower on March 10, 1959, to a seat on the
United States District Court for the Southern District of New York vacated by Judge
Lawrence Walsh. He was confirmed by the
United States Senate on September 9, 1959, and received his commission on September 10, 1959. He served as Chief Judge and as a member of the
Judicial Conference of the United States from 1980 to 1982. He assumed
senior status on May 31, 1982. He served as a Judge of the
United States Foreign Intelligence Surveillance Court from 1985 to 1989. His served on the bench until his death on April 8, 1989, due to a
cerebral hemorrhage in
White Plains, New York.
Rudy Giuliani was one of his law clerks. ==References==