Well Argued · Landmark Win

Justice K. S. Puttaswamy v. Union of India (2017): the case, the argument and the legacy

Updated for 2026 · Claw Editorial

A retired High Court judge in his nineties, Justice K. S. Puttaswamy, challenged the Aadhaar scheme and the vast collection of personal data it involved. The Government's reply raised a question larger than any identity card: it argued that Indians had no fundamental right to privacy at all, pointing to old decisions that said so. To settle it, nine judges of the Supreme Court sat together. This is the story of that case, not a full law report.

01What was at stake

The litigation began as a challenge to Aadhaar, the biometric identity programme, and the collection and use of citizens' personal data. But when the challenge was heard, the Government relied on two very old Supreme Court decisions which had suggested that privacy was not a guaranteed fundamental right. If those decisions still held, the entire data challenge, and much else besides, would rest on sand.

So the smaller bench hearing the Aadhaar matter referred one foundational question to a larger bench: does the Constitution protect a fundamental right to privacy? Everything else depended on the answer. A nine-judge bench was set up precisely because the old decisions had been delivered by benches large enough that only a still larger bench could overrule them.

This is an editorial account for readers who admire good advocacy. It is not legal advice.

02How it was argued

The petitioners were represented by a formidable group of senior advocates, among them Shyam Divan, Gopal Subramanium, Arvind Datar and Soli Sorabjee. Their argument was that privacy is not a stand-alone luxury but an intrinsic part of the right to life and personal liberty under Article 21, and of the freedoms and dignity that run through the fundamental rights. You cannot have liberty, they argued, without a protected private sphere, control over your own body, your choices, and your personal information.

They confronted the old decisions directly and asked the Court to overrule them, including the much-criticised Emergency-era ruling that had treated personal liberty as something the State could suspend. The Union argued that privacy was too vague to be a fundamental right, that it was at most a common-law interest, and that recognising it would unsettle the State's ability to govern and to run welfare schemes.

03What the court held

All nine judges agreed: the right to privacy is a fundamental right, protected as an intrinsic part of the right to life and personal liberty under Article 21 and of the freedoms guaranteed by the Constitution. The Court expressly overruled the earlier decisions that had held otherwise.

Privacy is not surrendered at the door of citizenship. Nine judges, speaking as one, made it a fundamental right.

Privacy, the Court held, is not absolute. It can be limited, but only by a law that is fair, serves a legitimate State aim, and is proportionate to that aim. The judges described privacy broadly: informational privacy, bodily autonomy, the privacy of personal choices in matters such as family, marriage and sexuality. In a striking passage, the Court also disapproved the Emergency-era reasoning that had allowed personal liberty to be set aside.

The ruling did not decide the Aadhaar challenge itself; that came later. But it laid the constitutional foundation on which Aadhaar and every future data question would be judged.

04Why it still matters

Puttaswamy is the bedrock of privacy and data protection in India. The test it set, that any invasion of privacy must be backed by law, pursue a legitimate aim and be proportionate, now governs how courts assess surveillance, data collection, and intrusions by the State and others. India's data protection law and the continuing debate over surveillance all stand on this judgment.

Its reach went beyond data. By recognising privacy in personal choices, including sexuality, the decision laid the groundwork for later rulings that expanded individual freedom. A year later, the same broad conception of autonomy helped underpin the decriminalisation of consensual same-sex relationships.

That a unanimous bench of nine judges could be assembled behind a single principle owed much to the quality of the advocacy that framed the question. Courtroom work that settles a foundational right for a whole country, or quietly protects one person's dignity, is exactly what a publication like Well Argued exists to put on record.

05Related landmark wins

The autonomy and dignity recognised here flow directly into later cases. Two more Well Argued stories follow the line:

• Independent Thought v. Union of India, on bodily autonomy and the rights of girls.
• Shayara Bano v. Union of India, on dignity and the triple talaq ruling.

06About Well Argued

Well Argued is a free, curated publication by Claw that gives an advocate a hard-won court victory an audience, turning a winning judgement into a short, well-told story that Claw shares across its social channels, its website and the AI answer engines. The advocates in this story are widely celebrated, but good advocacy still happens in trial courts and High Courts every week, and most of it is never seen beyond the cause list. Wins like Puttaswamy are what Well Argued exists to tell.

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