K.S. Puttaswamy v. Union of India (Right to Privacy Case)

A retired judge's challenge to the Aadhaar biometric identity scheme forced the Supreme Court to answer a question it had dodged for decades: is there a fundamental right to privacy in a Constitution that never once uses the word? Nine judges, writing six separate opinions, answered with one voice.

Parties

Justice K.S. Puttaswamy (Retd.) and another — petitioners; a retired High Court judge challenging the constitutional validity of the Aadhaar biometric identification scheme.

Union of India and others — respondents; the central government defending Aadhaar and, more fundamentally, contesting the existence of a standalone fundamental right to privacy.

Facts

Justice K.S. Puttaswamy, a retired judge of the Karnataka High Court, filed a writ petition challenging the constitutional validity of the Aadhaar scheme, under which the Union Government collected biometric and demographic data from residents to issue a unique identification number, later linked to a wide range of government welfare schemes and services. Among the grounds of challenge was the contention that mandatory collection and storage of biometric data violated citizens' right to privacy. During the hearing, the Union Government argued that no fundamental right to privacy existed under the Indian Constitution at all, relying on two earlier decisions — M.P. Sharma v. Satish Chandra (1954), an eight-judge bench decision, and Kharak Singh v. State of U.P. (1962), a six-judge bench decision — both of which had held, in different contexts, that the Constitution did not guarantee a distinct fundamental right to privacy. Given the conflict between these larger benches and a series of smaller, later benches that had assumed or recognised some form of privacy right, the question was referred to a nine-judge bench for authoritative resolution, independent of and prior to deciding the Aadhaar scheme's own validity.

Issues Raised

1. Is the right to privacy a fundamental right guaranteed under Part III of the Constitution of India?
2. Were M.P. Sharma v. Satish Chandra (1954) and Kharak Singh v. State of U.P. (1962), which had held or suggested that no such fundamental right existed, correctly decided?
3. If privacy is a fundamental right, from which provision or provisions of the Constitution does it flow, and what is its scope?

Arguments Contended

On behalf of Justice K.S. Puttaswamy and other petitioners: It was argued that privacy is an intrinsic and inalienable aspect of human dignity and personal autonomy, essential to the meaningful exercise of virtually every other Fundamental Right — freedom of speech, movement, association, and above all the right to life and personal liberty under Article 21 as expansively interpreted since Maneka Gandhi v. Union of India — and that M.P. Sharma and Kharak Singh, decided in a different constitutional era before Article 21's transformation, could not be treated as settling the question for all time; a constitutional democracy's guarantee of liberty was hollow without a corresponding right to privacy protecting the individual's personal and family life, bodily autonomy, and informational self-determination from unwarranted State intrusion.

On behalf of the Union of India (Respondent): It was argued that the Constitution, unlike some other national constitutions, contains no express textual guarantee of a right to privacy, that M.P. Sharma and Kharak Singh had authoritatively held no such distinct right existed, and that recognising an unenumerated, freestanding fundamental right to privacy risked significant, unpredictable expansion of judicial power to override legitimate State regulatory and welfare functions, including schemes like Aadhaar designed to improve delivery of welfare benefits and prevent leakage and fraud.

Court's Reasoning

The nine-judge bench held, unanimously though through six separate concurring opinions reflecting different doctrinal routes to the same conclusion, that 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 as part of the freedoms guaranteed by Part III more broadly. The Court reasoned that privacy is not a Western import or an elite luxury but a foundational condition for individual dignity, autonomy, and the meaningful enjoyment of every other constitutional freedom; it encompasses, at minimum, decisional autonomy over intimate personal choices, informational privacy over personal data, and bodily integrity and autonomy, though the Court did not attempt to exhaustively define its outer limits, leaving its precise contours to be developed case by case, as with other facets of Article 21.

The Court expressly overruled M.P. Sharma v. Satish Chandra and Kharak Singh v. State of U.P. to the extent they held or suggested that no fundamental right to privacy existed, holding that both decisions failed to account for the interconnected, evolving understanding of Fundamental Rights that had developed since Maneka Gandhi v. Union of India read Articles 14, 19 and 21 together and required State action to be fair, just and reasonable. Like other rights under Article 21, the Court held that privacy is not absolute and may be restricted by a law that satisfies the requirements of legality, a legitimate State aim, and proportionality between the means adopted and the object sought to be achieved — a three-part test subsequently applied by courts (and referred to, though not directly decided here, in the later stages of the Aadhaar litigation itself).

Judgement

The nine-judge bench unanimously held that the right to privacy is a fundamental right, intrinsic to the right to life and personal liberty under Article 21 and other freedoms in Part III of the Constitution, expressly overruling M.P. Sharma v. Satish Chandra (1954) and Kharak Singh v. State of U.P. (1962) to the extent they had held otherwise.

Legal Principle / Ratio

The right to privacy is a fundamental right, protected as an intrinsic part of the right to life and personal liberty guaranteed under Article 21 and as part of the freedoms guaranteed elsewhere in Part III of the Constitution. It is not an absolute right and may be restricted by State action that satisfies a three-part test: the restriction must be backed by law (legality), pursue a legitimate State aim, and be proportionate to that aim.

Significance

K.S. Puttaswamy v. Union of India is one of the most significant Indian constitutional judgments of the twenty-first century, resolving decades of doctrinal uncertainty by formally recognising privacy as a fundamental right and overruling two earlier large-bench decisions that had denied it. The judgment provided the constitutional foundation for the subsequent Aadhaar validity litigation, for the decriminalisation of consensual same-sex relations in Navtej Singh Johar v. Union of India (2018) (which relied heavily on Puttaswamy's dignity and autonomy reasoning), and for the data protection framework that eventually culminated in the Digital Personal Data Protection Act, 2023. It stands, alongside Maneka Gandhi v. Union of India, as one of the clearest illustrations of Article 21's continuing expansion through judicial interpretation, and its proportionality test has become a standard tool for testing the validity of State action restricting any of the rights read into Article 21.

Exam-Important Points

• Facts in one line: a challenge to the Aadhaar biometric scheme required the Court to first settle whether a fundamental right to privacy exists at all.
• Holding: privacy is a fundamental right, intrinsic to Article 21 and Part III generally — decided by a nine-judge bench, unanimously (six separate concurring opinions).
• Key principle: privacy is not absolute — restrictions must satisfy a three-part test: legality, legitimate aim, and proportionality.
• Overruled M.P. Sharma v. Satish Chandra (1954, 8 judges) and Kharak Singh v. State of U.P. (1962, 6 judges).
• Provided the constitutional foundation for Navtej Singh Johar v. Union of India (2018) and India's data protection law — a favourite for questions on Article 21's continuing expansion.

Facts, bench and citation verified against IndianKanoon's report of the judgment and independent case-law summaries.