Some of the world's largest music festivals-including SXSW, Coachella, Pitchfork, and Bonnaroo- promised that they will not use facial recognition technology at their events.So far 40 have agreed the policy following a campaign by high-profile musicians.”It's so important that people don't just learn about how scary and dangerous surveillance technology like facial recognition is but also learn about successful efforts to stop it,” Evan Greer, the deputy director of Fight For the Future, a digital rights rights advocacy group that spearheaded the campaign, told Motherboard.Rage Against the Machine's Tom Morello, the Glitch Mob, and Speedy Ortiz were leading voices in the campaign, demanding concert promoters ban technologies that can be used to police concertgoers for drug use, target individuals for specific advertising content, or worse. “I don't want Big Brother at my shows targeting fans for harassment, deportation, or arrest,” Morello tweeted in September.