The court crucially said that the right to privacy does not necessarily co-exist with data protection.

"Can this court define privacy? You can't make a catalogue of what constitutes privacy. Privacy is so amorphous and includes everything... if we make any attempt to catalogue privacy it will have disastrous consequences," said the constitution bench.

Justice DY Chandrachud, the judge who made these observations, said, "If I decide to co-habit with my wife, police can't barge into my bedroom. That's my privacy. Whether to send my children to school is not privacy because I have to send them to school under the Right to Education law."

Petitioners argued today that privacy is the heart and soul of the Constitution and is embedded in the rights to dignity and liberty.

To bolster their argument, they referred to Finance Minister Arun Jaitley's statement in Parliament in March. "The present bill (Aadhaar) pre-supposes and is based on a premise that it is too late in the day to contend that privacy is not a fundamental right. So I do accept that probably privacy is a fundamental right." According to news agency IANS, he told Rajya Sabha that "it is now accepted privacy is a part of individual liberty" and "let us assume that privacy is a part of liberty and no person shall be deprived of privacy without due process of law".

Representing the petitioners, senior lawyer Gopal Subramanium argued that the rights to life and liberty are pre-existing natural rights.

Petitions challenging Aadhaar say data like iris scans and fingerprints taken by the state violate citizens' privacy.

The Centre has said in court that the right to privacy is not in the Constitution and is not a part of the right to life.

The government's stand was criticised by opposition leaders like CPM's Sitaram Yechury, who tweeted: "We have a government which believes in the right to privacy for top loan defaulters from being named, but not in Privacy for ordinary citizens. Right to Privacy of the ordinary Indian cannot be invaded by any government. Every Indian's dignity is important." An eight-judge bench in 1954 and a six-judge bench in 1962 had both ruled that there is no right to privacy. After the mid-1970s, benches of two and three judges have consistently taken the position that privacy is indeed a fundamental right.