To buy subsidized grain in some states, for example, a beneficiary must authenticate her identity by placing the tip of a finger on a hand-held machine. Collecting a readable fingerprint this way requires functioning electricity, an internet connection and operational servers. In large swathes of rural India, such as in Rajasthan, all of this is a steep ask. Yet if any one of these steps fail, applicants are denied food assistance.

Previously, an infirm, older person could send a relative or neighbor with the relevant paperwork as a proxy to collect monthly rations. Now, the biometric identification system requires one’s physical presence.

In 2017, several economists and I conducted a survey of 900 households in Jharkhand, comparing villages that did and did not implement the Aadhaar system for buying grain. We discovered that the percentage of households that failed to obtain any grain at all was five times higher in the villages where Aadhaar authentication was compulsory (20 percent) than in those where it was not (4 percent).

In theory, biometric identification could help reduce identity fraud, but there has never been much evidence of large-scale identity fraud in India’s welfare programs.

The main problem with, say, the main food aid program is that officials and intermediaries appear to misreport official disbursements and skim off some of the aid. In a survey of about 2,000 randomly selected households in eight Indian states that the economist Jean Drèze and I conducted in 2013, the households collected only 87 percent of their entitlements; the rest of the resources were misdirected.

There is no evidence that Aadhaar has put a dent in corruption. In our 2017 survey, we found that among households that succeeded in buying grain, skimming levels were the same — about 7 percent — in villages with or without the Aadhaar system.

Despite these problems, the administration of Prime Minister Narendra Modi has expanded the reach of Aadhaar over the past year, requiring it for a host of public services beyond welfare benefits — such as to register marriages or file income tax returns.