He practised in both original and appellate courts, and appeared in several cases of political significance at the time involving constitutional, administrative, election and human rights law.

[8] In his annual report for that year, he described the judicial system of Ceylon at the time as “an antique labyrinth with tortuous passages and cavities through which the potential litigant must grope, often blindfolded, in his search for justice”.

Awarded a UNESCO Youth Leadership Grant in 1966, he studied the working of non-governmental organisations in western and eastern Europe, and was attached to the legal staff of the International Commission of Jurists, Geneva, then headed by secretary-general Sean MacBride.

He played a major role in the establishment of a Criminal Justice Commission for the trial of over 16,000 persons who were arrested, or had surrendered, in the wake of the 1971 JVP Insurrection, and was then responsible for overseeing their rehabilitation and return to society.

In the same year, he was awarded the degree of Doctor of Philosophy by the University of London (School of Oriental and African Studies) for his research on the application of international human rights law.

He chaired the Hong Kong Section of the International Commission of Jurists and was the principal commentator on constitutional, judicial and human rights issues in that territory in the period preceding the transfer of sovereignty.

[8] In 1996, Dr Jayawickrama, whose contract was due to end on 30 June 1997, was invited by the vice-chancellor, Professor Wang Gungwu, to apply for an extension under a scheme that was designed to encourage expatriate academics to remain in Hong Kong after the transfer of sovereignty to China.

Then, following a series of trenchant newspaper articles in which he questioned the legality of the provisional legislature and moves to repeal sections of the Bill of Rights, he was told he no longer met the minimum criteria for reappointment.

One of the first acts of the vice-chancellor of the university, Professor Cheng Yiu-chung, appointed in early 1997, was to order democracy slogans, originally painted by students following the 1989 Tiananmen massacre, and regularly repainted since, to be obliterated.

"[13] In October 1997, following his controversial and much publicised departure from the University of Hong Kong, Dr Jayawickrama was appointed Executive Director of Transparency International in Berlin.

He served as general counsel, and coordinated a programme on strengthening integrity systems in seven countries in Asia, Africa, Eastern Europe and Latin America.

His work, under UN or EU auspices, has involved collaboration with several governments, legislatures and judiciaries, including those of Libya, China, the Russian Federation, Lebanon, Nigeria, Kenya, the Seychelles, Turkey, Afghanistan, Iraq, Sierra Leone, Indonesia, the Pacific Island States, the Philippines, Armenia and Egypt.

He has published widely in refereed books and journals, and made presentations in over 40 countries on a range of issues relating to human rights, constitutional law, judicial integrity and governance.

Their elder daughter, Nishana Jayawickrama, who is married to Antony Jackson, is Adviser and Head, Asia and Europe, in the Political Affairs Division of the Commonwealth Secretariat, London.

Their younger daughter, Sharanya Jayawickrama, who was married to Barry Crosbie, was an assistant professor at Hong Kong Shue Yan University until her death in September, 2019.