International Judicial Monitor
Published by the International Judicial Academy, Washington, D.C., with assistance from the
American Society of International Law

Summer 2010 Issue

Leading Figures in International Law


Philip C. Jessup

By: Carolyn Dubay, Associate Editor, International Judicial Monitor

Mary Robinson

Philip Caryl Jessup was born on January 31, 1897 in New York City and is remembered as one of the most respected American international legal scholars of his time.  Although primarily an academic and diplomat, Jessup’s career is marked by an intense commitment to public service and a central role in the development of today’s leading international legal organizations.

A born New Yorker, Jessup attended Hamilton College and graduated in 1919, leaving briefly to serve in the army during World War I.  Jessup’s time at Hamilton College was particularly influential because it was there that Jessup met his early mentor, Elihu Root, former Secretary of State and Secretary of War.  Root, who served as the first president of the American Society of International Law, sparked Jessup’s interest in international law and introduced him to a number of prominent international legal scholars at the time.  Jessup was so influenced by Root, he later wrote a two volume biography of him published in 1938.

After his graduation from Hamilton College, Jessup decided to pursue a legal career and initially attended Columbia Law School, where he studied international law.  He later transferred to Yale and received his law degree in 1924.  Following a year as the assistant to the solicitor at the State Department, Jessup then decided to pursue his Ph.D. at Columbia, which he received in 1927.  During this time, Jessup also worked in private practice with a New York law firm.

Following his doctorate program, Jessup became a prolific author, writing books on maritime jurisdiction, the law of the sea, the doctrine of neutrality, and several books on American foreign policy.  Because of his keen intellect and savvy skills as a negotiator, Jessup’s early career was further marked by many opportunities to serve in government and scholarly positions.  In 1929, Jessup served as an assistant to Elihu Root at a conference of jurists on the revision to the Statute of the Permanent Court of International Justice.  By the mid-1930s, as international tensions rose, Jessup became more involved in politics and foreign policy.  He joined both the Institute of Pacific Relations (to study foreign policy problems involving China), and the American affiliate of this group, the American Institute of Pacific Relations.  In 1939, he was elected chairman of both organizations.  He was also a strong advocate of neutrality and non-intervention in the European and Asian wars and joined the America First Committee in 1941.  Despite his anti-war stance, after the United States entered World War II, Jessup became Associate Director of the Naval School of Military Government and Administration at Columbia University, and later a lecturer at the analogous army school in Charlottesville, Virginia.

Always respected and ready to serve the government, Jessup played a critical role in drafting the charters and statutes that formed many of today’s leading international organizations.   Jessup’s initial work began in 1943, when he was named the chief of training and personnel at the State Department’s Office for Foreign Relief and Rehabilitation (which later became the United Nations Relief and Rehabilitation Administration).  Working with the State Department in the 1940s, Jessup also served as assistant secretary at the Bretton Woods Conference in 1944 that resulted in the formation of the World Bank and the International Monetary Fund.  Following World War II, Jessup participated in the development of the statute of the International Court of Justice and served on the Committee on the Codification and Progressive Development of International Law, which drafted the statute of the International Law Commission.  Jessup’s dedication to research and scholarly pursuits during this time kept him deeply tied to Columbia Law School, where he was appointed the Hamilton Fish Professor of International Law and Diplomacy.  In 1948, he published his much-acclaimed book The Modern Law of Nations.

Not only did Jessup have an active role in developing the legal structures of the United Nations, he became a skilled diplomat in that arena.  In 1948, he was appointed deputy U.S. representative to the United Nations Security Council and from 1949 to 1953, he served as ambassador-at-large, in which capacity he was embroiled in numerous diplomatic negotiations during the growing tensions between the United States and the Soviet Union.  From his vast experience in United Nations negotiations, Jessup later wrote a series of Hague Academy lectures entitled Parliamentary Diplomacy on procedure and politics at the United Nations.  Years later, in 1974, Jessup also wrote The Birth of Nations, which described in detail many of the diplomatic and political struggles within the post-war United Nations, including efforts to develop a trusteeship for a Palestinian territory as a resolution to the Arab-Israeli conflict.

Jessup’s career was sadly marred during the height of McCarthyism in the 1950s.  Senator Joseph McCarthy identified Jessup in the early 1950s as a Communist sympathizer, despite the fact that Jessup had led many of the diplomatic efforts against the Soviets in the United Nations.  McCarthy’s attacks focused on Jessup’s experience in Pacific affairs and his role in preparing the State Department's "White Paper" on China. Although the Loyalty Board of the State Department cleared Jessup of all charges, Senator McCarthy continued to attack Jessup in the press, which had significant political consequences for his career.  In 1951, Jessup failed to gain Senate approval as the United States’ representative to the United Nations, despite support from President Truman and the most respected scholars and diplomats at the time, and despite Jessup’s formidable experience there.

Overcoming the obstacles posed by McCarthy’s tactics, Truman granted Jessup a one year recess appointment to the post in 1952.  Jessup then returned to academia in 1953 at Columbia Law School and became a symbol of resistance to the McCarthy movement.  In 1955, he was elected President of the American Society of International Law, and in 1959, Vice President of the Institut de Droit International.

During his career, Jessup expressed the belief that judicial institutions would have the principal role in preventing conflicts between nations.  It is not surprising, therefore, that Jessup eventually served as the American judge on the International Court of Justice shortly after President Kennedy took office.  Jessup served with distinction as a judge on the World Court from 1961 to 1970.  

Following Jessup’s tenure on the International Court of Justice, he returned to lecturing and occasional advocacy at the international level.  It was during this time that he wrote two of his most successful books, The Price of International Justice (1971) and The Birth of Nations (1974).  

Throughout Jessup’s career, he also remained active in the American Society of International Law, which named a global moot court competition in international law in his honor.  The Philip C. Jessup International Law Moot Court Competition recently celebrated its 50th anniversary and is the world's largest moot court competition, with participants from over 500 law schools in more than 80 countries. 

Jessup died on January 31, 1986.

For more detailed information on Philip Jessup’s life and career, see Oscar Schachter, Philip Jessup’s Life and Ideas, American Journal of International Law, Vol. 80, No. 4 (Oct. 1986), pp. 878-895.


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