New Delhi: Coming out with a strong defence of the need to make Aadhaar compulsory though there were other valid documents available, counsel for the Unique Identification Authority of India (UIDAI) said it was to prevent impersonation.

UIDAI counsel and additional solicitor general Tushar Mehta put up a stout defence before the five-judge constitution bench of the Supreme Court hearing petitions challenging Aadhaar and its enabling 2016 law.

Justice D.Y. Chandrachud, part of the bench, wondered why Aadhaar was being extended to mutual funds and insurance policies when there was no provision under the Prevention of Money Laundering Act (PMLA) to render a validly opened account non-operational.

Mehta said the linking would not involve a permanent closure of the account and was being done in the “larger public interest".

“We have a zero tolerance policy when it comes to money laundering. Public interest here is the interest of the nation," he added.

As the bench raised questions on surveillance, they were told by senior advocate Rakesh Dwivedi, also a counsel for the identification authority, that the government did not need Aadhaar for the purpose.

“If the government wishes to surveil, it will do so without Aadhaar," he said.

Regarding use of stored metadata by UIDAI, Dwivedi said that the metadata was of authentication records and did not reveal anything about individuals.

On 10 April, UIDAI told the top court that Aadhaar would help prevent duplication of PAN cards by linking databases.

Curbing terrorism, money laundering, black money and delivery of subsidies and benefits have been listed by the Centre as “legitimate state interests" in rolling out Aadhaar.

The matter will be heard next on 17 April.