Will Aadhaar, the 12-digit biometric-based unique identification number that the government wants every citizen to possess, lead to “mass surveillance” and create a “stalking culture” by the government, the Supreme Court asked the Centre on Wednesday as it posed six questions to the attorney general.

The questions from the five-judge Constitution bench headed by Chief Justice Dipak Misra were based on the arguments of 30 petitioners who have challenged the constitutional validity of the project. Attorney General KK Venugopal began his arguments for the Centre on Wednesday after the bench concluded hearing the petitioners a day earlier.

The Supreme Court’s six questions covered matters ranging from inclusion for government benefits to privacy and data security, the Hindustan Times reported. The court asked if the Centre could impose a project on citizens who may want to opt out, and whether or not the data collected on individuals before the Aadhaar Act was passed in 2016 should be destroyed.

It asked if the government had put in place measures to protect the data it has collected under the project and, finally, if the steps to secure the data could prove counter-productive, the report said.

The Chief Justice also summarised the petitioners’ arguments, put forth over two months, by identifying 10 points that needed to be addressed, The Times of India reported.

The Centre’s arguments on Wednesday focused on Aadhaar as an “enabler for millions of residents” as it would enable their right to food, livelihood and pensions. The Centre used this point to object to the petitioners’ concerns about privacy. The attorney general told the court the object of the Aadhaar Act was “targeted delivery for genuine beneficiaries” and that the scheme “furthers Article 21 right of the poor people of India, and advances the Directive Principles”. Article 21 is a fundamental right pertaining to the right to life and personal liberty.

The bench then asked the Centre if people without the biometric ID would be denied benefits of state welfare programmes. Venugopal said the government will not deny citizens any benefits they are entitled to as long as they have an alternative ID proof.

The court also referred to the petitioners’ arguments about many pensioners being denied their pensions, The Times of India reported.

“There is no question of a bogus pension account, which nobody other than the individual operates,” the court pointed out. Justice DY Chandrachud said, “There is a category of persons who suffer from Alzheimer’s disease and may have serious dementia. There are those old persons whose biometrics do not match with the Aadhaar data. Where do they go?”

The Centre responded saying the Aadhaar had helped root out bogus pensioners drawing post-retirement benefits for years.

The bench said the Aadhaar could not become a tool of financial exclusion, and pointed out instances where biometrics of manual labourers did not match with that of their Aadhaar data. The court said in remote areas, authentication may fail because of poor electricity or network connectivity. “Should the beneficiary be denied financial benefits?” the court asked, adding, “We will appreciate it if the government can tell us upfront that there is a serious issue of financial exclusion.”

On the question of data security, the court asked Venugopal why India could not follow Singapore’s unique identity number model – where every citizen’s information is in the form of an individual chip. “If it is meant for identification, why do you want to store data,” the court asked.

The hearing will continue on Thursday.