This desire to open up the lives of citizens and create visible and invisible links between their spending habits, their voter IDs, the state of their health and how they travel reveals the Indian government’s astonishing hunger for citizen data. The evidence of this hunger lies not just in Aadhaar but also in demands made by several government bodies. A federal body that conducts and manages high school examinations asked students to list their parents’ Aadhaar number, income, weight, height, birth year and blood group.

The reasons and justifications for Aadhaar and data collection have been couched by the project’s backers in the emotive language of country, pride and security. It is a useful tack because data frequently used in its support have been disputed. A World Bank estimate that the system saved $11 billion a year was found by the economists Jean Drèze and Reetika Khera to be false. India’s then-chief economist, Arvind Subramanian, cited a study showing $2 billion in savings and later clarified that the savings weren’t real but potential.

And what of technology’s detrimental effects? After the judgment, Nikhil Dey, a labor rights and information rights activist who challenged the project in court, gave voice to longstanding frustrations of economists, activists and researchers who work in villages when he wished that Aadhaar “had been made mandatory for something that affected the middle class the way the poor have been affected for the last four to five years.”

Several Indian states had made Aadhaar mandatory for the poor to receive much-needed benefits such as subsidized food and pensions. But failures of infrastructure and technology cut off large numbers of India’s poor from their benefits — the consequences, in the worst cases, even lead to deaths from starvation. Activists fear the court’s decision to allow linking welfare schemes with Aadhaar will continue to exclude people from what is already a threadbare safety net.

The questions about how the Aadhaar data would be used and whether citizens would be profiled and surveilled became more urgent after a raft of industrialists and government officials spoke about data being the new oil and the financial possibilities of monetizing the data of more than a billion people. At an event in the southern Indian city of Cochin in April, Nandan Nilekani, the technology entrepreneur and founder of the Aadhaar project, celebrated it as a tool for identification to the audience, arguing that “in the digital world, proving who you are is the essence of participation, otherwise you have fraud and fake news and bots and all that.”

The idea of Indians identifying themselves to participate online is a dangerous one. Anonymity in India is, as anywhere else, crucial to free expression. Indeed, it becomes particularly more important in places like India, where tolerance for free expression is low. People have been arrested for making jokes on social media and cartoonists have faced charges of sedition.

Supreme Court Justice Dhananjaya Y. Chandrachud, who wrote the dissenting judgment, gave voice to these fears: “When Aadhaar is seeded into every database, it becomes a bridge across discreet data silos, which allows anyone with access to this information to reconstruct a profile of an individual’s life.”

Although the Supreme Court upheld the Aadhaar program, Justice Chandrachud’s dissenting judgment is of great importance. It articulated the nature of the relationship between technology and power and that the collection of citizens’ personal information at Aadhaar’s scale could be used for surveillance. He was critical of how data was demanded, controlled, and protected. Justice Chandrachud’s dissent will be vital to judicial challenges in the future.

Rahul Bhatia is working on a book about technology in India.

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