[1][5] His practice became very successful and Nadesan appeared in some of the most famous legal cases in Ceylonese history: Abdul Aziz sedition (1943); Abdul Aziz criminal trespass (1959); Press Council Bill (1972); Pavidi Handa (Voice of Clergy) fundamental review (1982); Saturday Review/Aththa ban fundamental review (1983); Paul Nallanayagam treason case (1986).

[1][5] Following the problems caused by the Sinhala Only Act Nadesan wrote a series of articles Sunday Observer in which he argued that conflict between the Sinhalese and Tamil nations could only be resolved by democratic principles such as bilingualism, federalism, regional autonomy and constitutional safeguards for minorities.

[2][3] In the senate he took part in debates on social and labour legislation, the national question, minority rights and citizenship of plantation workers.

[1][2] Despite his passionate defence of minority rights Nadesan remained aloof of Tamil nationalistic politics and was critical of the Vaddukoddai Resolution.

[2] He was a founding member of the Civil Rights Movement in 1971 and received the Peter Pillai Foundation award in 1983 for his promotion of social justice and the protection under privileged in society.