Medical Marijuana, Inc. v. Horn

Under this rule, Horn's injury was proximately caused by Medical Marijuana, Inc.'s fraudulent marketing—specifically the false representation that Dixie X contained no THC—rather than by the controlled substance violation itself. Although THC was present in the product's causal chain leading to his failed drug test and job loss, the Court found that the relevant proximate cause was the company's deceptive labeling, which induced Horn's reliance and set the harmful sequence in motion. By establishing this fraud-to-injury pathway, Horn could proceed with his RICO claim despite the CSA's general bar on claims "by reason of" controlled substance violations, since his injury flowed from commercial fraud rather than from use or effects of the substance itself. The decision thus turns on the factual inquiry into what actually caused the harm: deception about what the product contained, not the THC's pharmacological effects.