Updated

India's top court on Wednesday upheld the government's policy of issuing a 12-digit identification number to every citizen, but said it can't be made mandatory for services such as bank accounts, cellphone connections and school admissions.

The Supreme Court said in a 4-1 decision that the government could use it for tax purposes and providing benefits under multimillion-dollar welfare schemes like subsidized food items and cooking gas.

Prashan Bhushan, an attorney, said private organizations couldn't ask for it because of privacy concerns.

The Indian government has enrolled more than 90 percent of the country's 1.3 billion people since it launched the scheme in 2010 linking fingerprints, iris scans and photos of citizens to the unique 12-digit number.

Banks, mobile operators and the government itself started to require identification numbers to access various services.

Rich Indians generally possessed passports, driver's licenses or credit cards that establish who they are. But the poor often were forced to rely on electricity bills, ration cards, voting cards or letters from local officials.

The government policy aimed at making a citizen's identification number override all other prior identity proofs.

Justice A.K. Sikri, reading out the majority judgment, said the government should bring a robust data protection regime in place as early as possible, noting that the attack on the government scheme by the petitioners was "based on violation of constitutional rights which they felt led to a surveillance state."

Sikri, however, said there was no possibility of a person obtaining a duplicate identification number because an adequate defense mechanism was in place.

Justice D. Y. Chandrachud said the collection of data could lead to individual profiling of citizens and the data could be misused by a third party and private vendors without the consent of an individual.