A new “meta-data” study of a number of previous studies about marijuana’s effect on driving says a pot smoker who has toked in the last few hours has nearly double the odds of an car accident as a totally sober person.

Now, this meta-study still isn’t at the point where law enforcement may be able to determine what is an unsafe level of THC for marijuana field sobriety testing. But, we’re probably getting nearer there.

More food for thought, especially in states with medical marijuana laws, as the linked story notes.