Occasional cannabis consumers and controls "did not differ in internalizing psychopathology, cognitive functioning, or brain activity," the study concluded.
The study's authors determined that per se THC limits are "not supported by science," and that they risk "wrongly accusing" motorists who are neither impaired nor have recently consumed cannabis.
"Voters understand the importance of having the right to choose what cannabis policies work best for them without interference from the federal government."