Rex non potest peccare

Rex non potest peccare means the king can do no wrong. At English common law it meant that the Crown could not be sued in tort, because the King could neither commit a wrong nor authorise one, and so could not be vicariously liable for the torts of his servants. The rule was abolished in England by the Crown Proceedings Act, 1947, which made the Crown liable in tort broadly as a private person.

The maxim was never adopted as such in India. Article 300(1) of the Constitution provides that the Government of India may sue or be sued by the name of the Union of India, and a State Government by the name of the State, and that they may be sued in relation to their affairs in the like cases as the Dominion of India and the corresponding Provinces might have been sued if the Constitution had not been enacted. The extent of liability therefore traces back, through the Government of India Acts, to the liability of the East India Company.

Courts drew a distinction between sovereign and non-sovereign functions. In State of Rajasthan v. Vidyawati (1962), the State was held liable for the rash driving of a government jeep used for a non-sovereign purpose. In Kasturi Lal Ralia Ram Jain v. State of Uttar Pradesh (1965), the State was held not liable for loss of seized property by the police, because the power of arrest and seizure was sovereign. Later decisions, including N. Nagendra Rao and Co. v. State of Andhra Pradesh (1994), narrowed sovereign immunity and treated it as confined to functions such as defence, administration of justice and maintenance of law and order, and the Supreme Court has awarded compensation in public law for violation of fundamental rights.

A separate personal immunity exists under Article 361: the President and Governors are not answerable to any court for the exercise of the powers and duties of their office. Examiners test the meaning, the contrast with Article 300, and the sovereign and non-sovereign distinction.