Ex Ante vs Ex Post Facto Environmental Clearance: Prior Approval as the Rule and Post-Facto Clearance as the Exception

The whole idea of environmental impact assessment is to look before you leap: to assess impacts and hear affected people before a project is built. An ex ante (prior) environmental clearance serves that purpose. An ex post facto (post-facto or retrospective) clearance is granted after a project has already begun or been completed without clearance. Whether the law should ever allow the latter has been the most contested question in Indian EIA law, culminating in the Supreme Court's decision in Vanashakti v. Union of India (29 July 2026).

1. Ex Ante (Prior) Environmental Clearance

The EIA Notification, 2006 requires prior environmental clearance before any construction work, or preparation of land (other than securing the land), is started for a listed project, and before its expansion or modernisation. Prior clearance allows the regulator to consider alternatives (including not building at all), ensures that the public consultation is meaningful because options are still open, implements the precautionary principle, and prevents irreversible damage. It is the rule under Indian law, and projects that proceed without it are unlawful.

2. Ex Post Facto Environmental Clearance

An ex post facto clearance is granted to a project that has started or been completed without prior clearance ('violation cases'). Its supporters argue that demolition of completed projects wastes resources and can itself harm the environment, and that regularisation with penalties, remediation and strict conditions is more practical. Its critics argue that it rewards violators, makes EIA and public consultation meaningless, and undermines deterrence.

2.1 The judicial development

1. Common Cause v. Union of India, (2017) 9 SCC 499: mining without EC or beyond it was illegal, and the value of illegally extracted ore had to be paid;
2. Alembic Pharmaceuticals Ltd. v. Rohit Prajapati, (2020) 17 SCC 157: the concept of an ex post facto EC is contrary to the fundamental principles of environmental jurisprudence and an anathema to the EIA Notification; a 2002 circular permitting it was invalid, though the Court imposed compensation instead of closure;
3. Electrosteel Steels Ltd. v. Union of India (2021): ex post facto clearance should not ordinarily be granted but is not prohibited in all circumstances, and may be granted in exceptional cases in accordance with law;
4. Pahwa Plastics Pvt. Ltd. v. Dastak NGO (2022): units that had obtained post-facto clearance under the government's policy, and whose operations were otherwise permissible, were not ordered to close;
5. Vanashakti v. Union of India (16 May 2025): a two-judge bench struck down the 2017 notification and the 2021 office memorandum providing for post-facto clearance; this was recalled by a three-judge bench (2:1) on 18 November 2025 in CREDAI v. Vanashakti; and
6. Vanashakti v. Union of India (29 July 2026, Chief Justice Surya Kant and Justices Joymalya Bagchi and Vipul Pancholi): on a fresh hearing, the Court upheld the 2017 notification as a narrowly tailored, time-bound, one-time amnesty under Section 3 of the EPA, but quashed the 2021 office memorandum prospectively, because an administrative order cannot override delegated legislation and an open-ended regularisation regime was disproportionate and violated Article 14. Post-facto clearance may be provided only by statutory notification under Section 3, narrowly tailored and justified by supervening public interest.

3. Key Differences

4. Related Topics and Provisions