José Luis Jesus is a member of the Tribunal since 1 October 1999; re-elected as from 1 October 2008 and 1 October 2017; President of the Tribunal 2008–2011; President of the Seabed Disputes Chamber 2014-2017; Member of the Special Chamber formed to deal with the Dispute concerning delimitation of the maritime boundary between Mauritius and Maldives in the Indian Ocean (Mauritius/Maldives).

Delegate and Head of Cabo Verde delegation to the Third United Nations Conference on the Law of the Sea (1979–1982); Sixth Committee of the United Nations General Assembly (1979–1994); Counsellor (Legal Adviser) (1981–1987), Ambassador and Deputy Permanent Representative of Cabo Verde (1987–1991), Ambassador and Permanent Representative of Cabo Verde to the United Nations in New York (1991–1994); Chairman, Group of 77 for the Law of the Sea (1986); Chairman, Group of African States at the United Nations (1986); Head of the Cabo Verde delegation to United Nations Conference on the Law of Treaties between States and International Organizations or between International Organizations, Vienna (1986); Chairman, Preparatory Commission for the International Seabed Authority and for the International Tribunal for the Law of the Sea (1987–1995); President, United Nations Security Council (July 1992 and November 1993); Special Envoy of the Secretary-General of the United Nations for the Great Lakes Region, Central Africa (1994); Ambassador of Cabo Verde to Portugal, Spain and Israel (1994–1996); Secretary of State for Foreign Affairs and Cooperation (1996–1998); Minister of Foreign Affairs and Communities (1998–1999); Chairman, National Commission on the Delimitation of Maritime Boundaries, Cabo Verde; Legal Consultant for technical assistance in the drafting of fisheries legislation, FAO; Lecturer at several seminars and conferences on the law of the sea, international dispute settlement, humanitarian law and international relations.

Author of publications in the fields of the law of the sea, ITLOS proceedings and humanitarian law and extradition.