Definition
The operation of a law on facts, transactions, or rights that arose before the law was enacted — generally disfavoured in law, and specifically prohibited in criminal law (no ex post facto criminal punishment under Article 20(1)).
Retrospective operation occurs when a new law reaches back in time to affect past transactions or rights. There are three types: (a) purely retrospective — operates entirely on past events already concluded; (b) retroactive — creates new liability or consequences for past acts; (c) declaratory — declares what the law was, treating it as always having been thus. Article 20(1) of the Constitution absolutely prohibits ex post facto criminal laws — no one can be convicted for an act that was not an offence when committed, and punishment cannot exceed what was prescribed at the time. For civil/tax legislation, there is a strong presumption against retrospective operation — courts will not read a statute as retrospective unless the legislature has clearly stated this intent.
Statutory Definition
Article 20(1), Constitution of India: 'No person shall be convicted of any offence except for violation of a law in force at the time of the commission of the act charged as an offence, nor be subjected to a penalty greater than that which might have been inflicted under the law in force at the time of the commission of the offence.' This is the absolute constitutional bar on retrospective criminal law. Section 3(2), General Clauses Act, 1897 (for repeal): 'The repeal of an enactment shall not... affect any right, privilege, obligation, or liability acquired, accrued, or incurred under any enactment so repealed.'
Etymology & Origin
From Latin 'retrospicere' (to look back) from 'retro' (backwards) + 'specere' (to look). A retrospective law 'looks back' — it reaches behind its date of enactment to affect past events. The maxim 'lex prospicit non respicit' (law looks forward, not backward) captures the presumption against retrospective operation.
Full Legal Analysis
Retrospective Operation: The Law That Reaches Back
Laws are generally prospective — they govern future conduct. Retrospective laws are the exception: they change the legal consequences of acts that have already occurred. In criminal law, this is constitutionally prohibited — no one can be punished for an act that was lawful when committed. In civil and tax law, retrospective legislation is disfavoured but not constitutionally prohibited — provided it doesn’t take away vested rights without compensation.
Article 20(1): The Absolute Bar in Criminal Law
Article 20(1) has two limbs: (a) Non-retrospective criminalisation: No person can be convicted for an act that was not a crime when committed. If the act was lawful, the legislature cannot subsequently make it criminal and punish the person for the prior act. (b) Non-retrospective punishment: Even if the act was criminal when committed, the punishment cannot be increased by subsequent legislation — the person can only receive the maximum penalty that was prescribed at the time of the act. These two protections together ensure that citizens can plan their conduct in reliance on existing law.
Retrospective Tax Legislation
Tax legislation is sometimes made retrospective — particularly to close loopholes that were being exploited. The Finance Act 2012 (the Vodafone retrospective tax amendment) is the most controversial example: Parliament retrospectively amended the Income Tax Act to impose tax on indirect transfer of Indian assets in a foreign merger — targeting the Vodafone-Hutchison deal. The Supreme Court had held in Vodafone International Holdings v. Union of India (2012) 6 SCC 613 that no tax was due — Parliament then retrospectively amended the law to override the judgment. This was widely condemned as damaging to India's investment climate and was ultimately reversed by the government in 2021.
“Retrospective legislation breaks the fundamental contract between citizen and state: the citizen is entitled to rely on the law as it stands when they act. When the state changes the rules after the game, it betrays this reliance. In criminal law, Article 20(1) makes this betrayal unconstitutional. In civil law, it remains a legislative choice — but one that damages the rule of law every time it is made.”
This Term in Indian Statutes
Constitution of India, 1950
"No person shall be convicted of any offence except for violation of a law in force at the time of the commission of the act charged as an offence, nor be subjected to a penalty greater than that which might have been inflicted under the law in force at the time of the commission of the offence."
Article 20(1): absolute constitutional bar on retrospective criminal law — no ex post facto conviction or enhanced punishment
