He started his practice in 1926. Initially, he was working under his father-in-law, P. Venkata Raman Rao Naidu, who was junior ofthe Andhra Kesari Prakasam Pantulu. Later, he became the district munsiffor Bapatla. Guntur district. Following this, he started his independent practice with his brother-in-law and soon had a lot of clients flowing in from the state of Madras. Therefore, it wasn’t a surprise when he rose to the benchas the Madras High Court Judge in 1948.
In 1954, he served as the first Chancellor of the Sri Venkateswara University at Tirupati.However, a later amendment in the law prescribed the Chancellorship to the Governor of State and J. Subba Rao was replaced. It was an immense honour when he was elevated as the Chief Justice of Andhra Pradesh High Court in 1956. This made him the first Chief Justice of Andhra Pradesh High Court. Soon after this,he was appointed as the Supreme Court Judge in 1958. His rise within the judiciary, did not stop here. He went on to become the 9th Chief Justice of India in 1966. After a year’s service, he retired in 1967 in order to contest in the Presidential Elections as the unanimously chosen candidate of the opposition parties. However, he lost to Zakir Hussain.
For his contribution to the field of law, he was awarded Honorary Doctorate from Bangalore University. He was a highly disciplined man with vast knowledge.He has contributed majorly in the development of Constitutional Law. During his time at the Supreme Court, he gave a lot of importance to fundamental rights. His presence of mind and timely action in various cases had earned him are spectable position within the Judiciary. The most famous of his cases is the Golak Nath Case in which he emphasized on the importance of fundamental rights by calling them, “the primordial rights necessary for the development of human personality.”
Justice B.P. Jeevan Reddy on the centenary celebrations of Chief Justice K. Subba mentioned how he famously came to be known as the dissenting judge. Infact, it was said that some of his most notable judgments were his dissenting judgments. For instance, in Radeysham Khare v. State of M.P, he laid down the test for distinguishing the quasi-judicial functions of anadministrative body from its executive functions when it performs dual functions. In Kharak Singh v. State of U.P. he held, “It is true our constitution does not expressly declare a right to privacy as a fundamental right, but the said right is an essential ingredient of personal liberty.”
Finally, he was referred to as the ‘defender of liberties’ by V.D Mahajan, a revered historian and author, in his book, “Chief Justice K. Subba Rao: Defender of Liberties.”