Activists in the Indian capital of New Delhi are expressing concern over the use of facial recognition by the police amid intensifying protests over the controversial Citizenship Amendment Act (CAA).

The protesters are reportedly anxious about the lack of regulation around facial recognition and its possible role in the crackdown on the protest movement. They point to the fact that the government didn't acknowledge it was using the technology for this purpose until a national newspaper, The Indian Express, first broke the news in December.

Back then, the technology was used to identify and filter out what the police called "law and order suspects" at one of Prime Minister Narendra Modi's rallies.

When the Delhi Police first acquired its Automated Facial Recognition System (AFRS) in 2018, the original purpose was to identify and locate missing children by matching facial images.

Face masks, handkerchiefs and pseudonyms

"I do not know what they are going to do with my data," Rachita Taneja, a Delhi-based activist who created an online cartoon about cheap ways for protesters to hide their faces, told Reuters. "We need to protect ourselves, given how this government cracks down."

A 21-year-old Muslim protester told Reuters that he has adopted a pseudonym and at times covers his face with a handkerchief to avoid being identified.

"We don't know enough about these things, but we are trying to take some precautions," he said.

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The recently retired police chief of the northern state of Uttar Pradesh, O P Singh, told Reuters that facial recognition had only helped the police in detaining a "handful" of more than 1,100 people arrested on charges of alleged links to violence during protests.

Modi's government is currently seeking bids from companies to help set up a National Automated Facial Recognition System. It would match photos captured from CCTV with existing databases, with policing a key potential use for such technology. Critics equate the project with the far larger-scale surveillance system in China.

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However, software companies that have supplied facial recognition technology to police in various states dispute the prospect of mass surveillance.

Atul Rai, co-founder of Staqu — a tech company that supplies its Police Artificial Intelligence System to eight Indian states including Uttar Pradesh — told Reuters that worries about mass surveillance were exaggerated because of the difficulties of achieving this with a population exceeding 1.3 billion people. Although he added that there was a need for regulations to avoid potential issues.

"If somebody is throwing stones at a police officer, doesn't he have a right to take a video and identify him?" Tarun Wig, co-founder of Innefu that provides Delhi Police with the facial recognition software, told Reuters.

CAA particularly unpopular in Delhi

Protest movements have been galvanizing in different parts of the country against the Citizenship Amendment Act (CAA) which was passed in December by the Narendra Modi-led Hindu nationalist government. 

The CAA fast-tracks the naturalization of non-Muslim migrants that arrived in India from Pakistan, Bangladesh and Afghanistan before 2015. Critics argue that excluding Muslims defies India's secular constitution, Modi's government counters that Muslims are not a threatened minority in these three countries.

Shaheen Bagh, a Muslim-majority neighborhood in Delhi has become the epicenter of the protests.

dvv/msh (Reuters, dpa)