AI, brain scans and cameras: The spread of police surveillance tech

DUBAI, United Arab Emirates - A brain wave reader that can detect lies. Miniaturized cameras that sit inside vape pens and disposable coffee cups. Massive video cameras that zoom in more than a kilometer to capture faces and license plates.

At a police conference in Dubai in March, new technologies for the security forces of the future were up for sale. Far from the eyes of the general public, the event provided a rare look at what tools are now available to law enforcement around the world: better and harder-to-detect surveillance, facial recognition software that automatically tracks individuals across cities and computers to break into phones.

Advances in artificial intelligence, drones and facial recognition have created an increasingly global police surveillance business. Israeli hacking software, American investigation tools and Chinese computer vision...