A five-judge constitution bench headed by Chief Justice Dipak Misra, however, asked what the position will be with regard to breach, if any, that could have taken place between 2009, when the Aadhaar scheme was launched, and 2016 when the enabling law came into force.
The bench said the centre came out with the law in 2016 to negate the objection that it was collecting data since 2009 without any authorisation, but the issue which needed consideration was what will happen if the data collected earlier, have been compromised.
"Our (Privacy) judgement said that there has to be a law. They enacted a law to take away the basis of the argument. The absence of a law can be cured, but there may be other issues like whether the data collected (earlier) had the same statutory safeguards. What will happen in case of breach," the bench, also comprising Justices A K Sikri, A M Khanwilkar, D Y Chandrachud and Ashok Bhushan, said.
The bench is hearing a clutch of petitions including one filed by former High Court judge Justice K S Puttaswamy challenging the constitutional validity of the Centre's flagship Aadhaar scheme and its enabling 2016 Act.
Senior advocate Gopal Subramanium, appearing for the former judge, said the law cannot cure defects like invasion of fundamental rights of citizens and invasion of privacy in this case was "complete once you unlawfully collected information. All this cannot be cured."
On the issue of making Aadhaar mandatory for the poor to avail facilities, he said the state was making a "moral judgment on the poorest of the poor in saying they make ghost cards".
There are ways to detect and stop pilferages, he said, adding that fake persons can be identified and action taken against them, but "do not treat every person with indignity".
"Socio economic rights are complementary to political rights. The latter is not subservient to the form," he said, adding that the Aadhaar Act lacked both "substantive and procedural reasonableness".
Referring to a court judgement, he said "governments come and go and we do not know who will inherit this database even if we don't impute any malice to this government. This law will remain. The judges will have to keep that in mind."
The advancing of arguments remained inconclusive and would resume tomorrow.
Earlier, the senior lawyer had said that the State cannot sit in judgement and rely only on biometric details to establish the identity of its citizens. "Virtual person cannot reduce the real person-hood," he had said, dubbing the Aadhaar Act as "unconstitutional".
The individual's rights always gets primacy over the rights of the State and moreover, the action of the government is needed to be tested "for substantive and procedural due process", he had said.
The court had posed whether the government was not entitled to seek proof of identity from citizens if their entitlement to certain benefits were dependent upon their identities.
Senior advocate Kapil Sibal, appearing for the West Bengal government, had said the proof of identity has to be linked with the status of the person which entitles him or her for the benefit and moreover, the citizens must have the choice to prove their identity.
The top court had on December 15 last year extended till March 31 the deadline for mandatory linking of Aadhaar with various services and welfare schemes of all ministries and departments of the Centre, states and Union territories.