Three of America’s largest cannabis companies were accused in a class-action lawsuit filed on Monday of systematically advertising their products as medicine capable of treating mental health, pain, and other disorders while knowing that the science didn’t support those claims and that their products could even worsen the conditions they claimed marijuana could treat.

Patrick Kenneally, the plaintiffs’ lead attorney, said in an interview that the lawsuit’s aims are twofold: hold the cannabis industry accountable for “years of misrepresentation” of their products’ health benefits, and force them to “warn consumers about the well-known, obvious, and scientifically validated dangers of cannabis.”

The suit was filed in federal court in Illinois on behalf of consumers in 12 states. It could eventually include millions of plaintiffs. Between possible civil penalties, punitive damages, and even allegations that each company functions as an organized criminal enterprise, the stakes are enormous.