I took the NYT quote from Eduardo Romano to mean that after controlling for some of those confounding factors, there was no evidence of increased risk. I posted the NYT article because the abstract didn't mention much about marijuana specifically.

Specifically, drivers who test positive for marijuana or self-report using marijuana are more than twice as likely as other drivers to be involved in motor vehicle crashes.

Without having read the study, do you know if this statistic controls for age or anything else? If so, I stand corrected.

Thanks for your polite tone, it's not every day I get called a "fucking moron" before 7 a.m. :)