Although subtler than handcuffs and prison time, the technology confronts one of the most stubborn challenges of bringing down sex trafficking: “the very ingrained fantasy in this culture about commercial sex in that everybody is a willing participant,” says Jennifer Long, founder of AEquitas, a nonprofit that works to improve the prosecution of human trafficking. Bradley Myles, head of Polaris, the NGO that runs the National Human Trafficking Hotline, agrees. “Even if men aren’t getting arrested, it’s piercing the anonymity of buying sex,” he says. “It’s a shock to the system.”