Discuss the principle of purpose limitation in State databases with reference to Aadhaar and the electoral roll. How can exclusion errors in welfare delivery be minimised?

Purpose limitation means that personal data collected for a stated purpose should be used only for that purpose. The Digital Personal Data Protection Act, 2023 writes this into law by tying processing to a "specified purpose" [5]. A recent Union proposal would replace Aadhaar with biometric-authenticated voter ID (EPIC) for scheme beneficiaries. This shows why databases built for one purpose cannot be freely reused for another.

Purpose limitation: Aadhaar vs the electoral roll

• Aadhaar's purpose is set by law: it exists for targeted delivery of subsidies. Section 7 allows authentication to be required, but its proviso guarantees an alternate means of identification [1].
• In Puttaswamy (2018), the Supreme Court upheld Aadhaar for welfare. It barred private use under Section 57 and required every State use to be backed by law [2].
• The electoral roll's purpose is the franchise (Articles 324 and 326; RP Act, 1950). In the Bihar SIR judgment (May 2026), the Court allowed the ECI only a limited citizenship enquiry, for electoral purposes. It held that deletion is not a declaration of non-citizenship [3].
• Why reuse fails: EPIC is derived from the roll, so roll errors would pass straight into welfare. Not every citizen is a voter: minors and unenrolled migrants would be excluded by design.
• Counterview: linking databases helps remove duplicates and reduce leakages, as under JAM. But it needs legal backing and must be proportionate.

Minimising exclusion errors

• Mandatory fallback: UIDAI's exception-handling rules let a person collect benefits by showing their Aadhaar and ration card when authentication fails. Each such case goes in an exception register that must be audited [4].
• Multiple ways to authenticate: OTP, iris or face; offline or less frequent checks reduce failures from worn fingerprints.
• Keep databases separate: removal from the electoral roll must never by itself remove anyone from PDS or other schemes.
• Time-bound grievance redress: NFSA vigilance committees and social audits; restore benefits first, verify later.
• Legal safeguards: any new data linkage should be authorised by a law and pass the Puttaswamy proportionality test [2].

Purpose limitation protects both privacy and entitlements. Welfare should rest on a law-backed identity system with humane fallbacks, not on a voter list. This is in keeping with the Article 21 right to food and dignity and SDG 2 (Zero Hunger).