Hair-brained legislation

Ohio ("Land of 10,000 Toxic Waste Dumps") has now joined Nevada and Indiana as states that have laws on the books prohibiting driving under the influence of THC, the most prevalent psychoactive chemical in marijuana. They test by taking a hair sample and checking to see if there's any THC metabolite present. This is idiotic (and legally absurd) on at least two counts:

1) THC metabolites are found in the body (fatty tissue, blood, urine, hair) weeks or months after any exposure to marijuana. So maybe you smoke a joint at midnight on New Year's Eve. You were high until around 1:30 or 2. Then you swear off smoking pot as your big resolution for 2006. But you get pulled over at a random traffic stop and busted for driving under the influence of marijuana in mid-March! Punishable by up to 6 months in jail, by the way. Yeah, that's a law that'll make the youngsters respect the legal system...

2) Back before he was "America's most famous doctor," Andrew Weil worked at the National Institues of Health doing research on altered states of consciousness. While there, he looked into the effects of marijuana smoking on driving skill. He found that drivers who had been given a chance to practice driving while high (which includes basically everyone who regularly uses grass), actually drove BETTER than drivers who smoked nothing at all. Given the state of governmental interference into drug-related research since the 70s, I doubt any further research has been done along these lines since then. So, the existing scientific research tells us that driving under the influence of marijuana is not a danger to other drivers, but could actually increase the overall safety of the roads.

Justice, anyone? Logic, even?