Justice Iyer is one of the versatile authors who has written on each and every aspect of law and beyond, maintaining lucidity and depicting ocean deep knowledge of the subject. His dynamic and enlightened idea on law and contemporary jurisprudence is a path-making source for the present and future judicial system. Out of multifarious activities of his life he always works out the time in writing for law and techno-socio matters, that becomes the flow of inspiration for the lawyers, judges and the common people, not only in our own land but also in other parts of the world. Justice Krishna Iyer was Home Minister and minister for law, power, prisons, irrigation and social welfare in the Government of the State of Kerala following the victory of the Communist Party of India under E. M. S. Namboodiripad in the 1957 elections. He won the Elections as an Independent, and later pledged support to the Communist government.He was the originator of Kerala Land Reforms Act, which drastically transformed the land holding pattern among the people of theState of Kerala. Iyer retired from politics in 1959.

Iyer became a judge of the High court of Kerala on 2 July 1968. He became a Judge of the Supreme Court of India in 1973. During this time, the Supreme Court interpreted Article 21 of the Constitution of India in the sense that the national government was obliged to provide free legal services to accused persons in custody. He retired from the Supreme Court in November 1980.

Iyer has rendered several important judgements involving the interpretation of the Constitution of India and the statutory as well as personal law of Muslims. Analysing and summarizing his judgements, a book titled "Muslim Law- An analysis of the judgments rendered by Justice V. R. Krishna Iyer" has been published in the year 2006.