How an advertising company put a ‘marijuana cookie’ on your computer to get weed legalized

“This kind of behavioral and demographic targeting has been going on [in business] since the early 2000s,” said Jonathan Mayer, a lawyer and computer scientist who specializes in privacy and security issues as a graduate fellow at Stanford University. “The private sector is now targeting people using precise geotargeting and beacons, which political campaigns are just starting to dabble in it. The news—good or bad—is that they are catching up quickly.”