As a student, he took part in various activities, including student politics. In 1945, he was elected as the General Secretary of The Presidency College Student Union. His leadership qualities were also exhibited when he was studying for the bar in London as he was selected for the post of General Secretary of the Indian Socialist Group in 1948.
He started his practice in 1949 from the Calcutta High Court where he mostly dealt with cases relating to Civil, Revenue and Constitutional law.In 1968, he became a judge of the Calcutta High Court, and in 1982 he worked as a member of the eighth Finance Commission.
In 1983, he became the acting Chief Justice of Calcutta High Court.Within a few weeks’ time since then, he was appointed as the Supreme Court Judge. In 1989, he was appointed as the Chief Justice of India. He is the only judge from the Calcutta High Court to have been appointed as the chief justice of India. However, he died while serving in office and couldn’t complete histerm. It was 1990 at the time, and he had served from a heart attack while on a lecture tour.
Honourable justice Sabyasachi Mukherjee was the chief justice at the time when the first proceedings of impeachment against a judge were initiated in the year 1993, in this case, Justice V Ramaswami under corruption charges.He had comprised a committee to look into the matter. However, he did not take any action against the judge and instead asked him to go on leave.
His other notable judgments include decisive decisions on matters of the law like in A.R. Antulay case where he stated that it should not be a well-settled principle of law to follow the doctrine of stare decisis in cases which were subjected to per incuriam. This decision helped in bringing more clarity to the binding nature of precedents.
In 1982, in the case of A.K.M. Hassamanuzaman & Ors. v.Union Of India & Ors, he was the only judge who was asked to he ara matter of electoral rolls urgently.In his judgment, he recorded that the Supreme Court was co-par with the High Court only as of the Constitutional Court. The appellate powers of the Supreme Court did not make it a superior right to which the High Court was subordinate. This helped maintain the integrity of the Constitutional courts.
However, one of his largely criticized decisions, is on the concept of contempt of court, in the case of P.N. Dua v. P. Shiv Shanker,1990. In this case, a cabinet minister of the Government of India was exonerated though he had compared the judges of the Supreme Court to anti-social elements. It was held that the statement did not affect the administration of justice and hence did not constitute contempt.