It was a risky move by the social network. Six years earlier, it had deactivated the technology in Europe after regulators there raised questions about its facial recognition consent system. Now, Facebook was reintroducing the service as part of an update of its user permission process in Europe.

Yet Facebook is taking a huge reputational risk in aggressively pushing the technology at a time when its data-mining practices are under heightened scrutiny in the United States and Europe. Already, more than a dozen privacy and consumer groups, and at least a few officials, argue that the company’s use of facial recognition has violated people’s privacy by not obtaining appropriate user consent.

The complaints add to the barrage of criticism facing the Silicon Valley giant over its handling of users’ personal details. Several American government agencies are currently investigating Facebook’s response to the harvesting of its users’ data by Cambridge Analytica, a political consulting firm.

Facebook’s push to spread facial recognition also puts the company at the center of a broader and intensifying debate about how the powerful technology should be handled. The technology can be used to remotely identify people by name without their knowledge or consent. While proponents view it as a high-tech tool to catch criminals, civil liberties experts warn it could enable a mass surveillance system.