The American Civil Liberties Union (ACLU) and 40 other groups on Tuesday demanded that Amazon stop allowing governments to use its Rekognition tool, which the company says can monitor “all faces in group photos, crowded events, and public places.” Existing customers include the city of Orlando and the Washington Country Sheriff’s Office in Oregon, which has built a database of 300,000 mugshot photos to use with Rekognition.

“With Rekognition, a government can now build a system to automate the identification and tracking of anyone,” the ACLU warned in a blog post.

“With this technology, police would be able to determine who attends protests. ICE could seek to continuously monitor immigrants as they embark on new lives. Cities might routinely track their own residents, whether they have reason to suspect criminal activity or not. As with other surveillance technologies, these systems are certain to be disproportionately aimed at minority communities.”

Amazon is defending its tech. “Our quality of life would be much worse today if we outlawed new technology because some people could choose to abuse the technology,” it said in a statement. “Imagine if customers couldn’t buy a computer because it was possible to use that computer for illegal purposes.”

The affair carries echoes of the storm at Google over that company’s “Project Maven” deal with the Pentagon. The deal sees Google supplying the U.S. military with “artificial intelligence” technology for sifting through drone video footage. Employees fear the tech could help target people for death, and some have resigned in protest.

It’s not like there hasn’t been outrage in the past over Big Tech’s links with the U.S. authorities. Edward Snowden’s revelations about programs such as Prism, through which major online platforms provide customer data to intelligence services, were explosive and widely absorbed—but that was a matter of legal compulsion.

Amazon and Google’s controversial deals are a commercial affair, and therefore even more open to criticism. Supplying technology to the military may not be an inherently bad thing—indeed, Google, IBM, Amazon and Microsoft are all currently jostling to sell cloud services to the Pentagon—but nobody is forcing these companies to supply more sensitive image-recognition technology to those who might use it in violation of human or civil rights.

It’s worth noting that some companies are very aware of the ethical considerations around the sale of their cutting-edge tools. Microsoft, for example, told Wired earlier this month that it has refused certain contracts that would have seen the company build custom AI systems, thanks to the deliberations of an internal ethics board.

Google has also talked about setting up new ethical principles to guide its sales. Then again, Google has also just removed any references to its old “Don’t be evil” motto from its employee code of conduct.

The U.S. is still a way off from mirroring the situation in China, where companies such as Alibaba are helping the government build a civil-rights-trampling “social credit” system that would involve mass surveillance with frequent real-life consequences. But the ties between America’s big tech firms and authorities are still clearly getting too cozy for many people inside and outside those corporations.