From Sam Smith's Progressive Review, another new way to break the law. :
DETROIT NEWS - Motorists can be prosecuted for driving under the influence of drugs if they test positive for any trace of marijuana, even weeks after they smoked it, the Michigan Supreme Court has ruled. In a 4-3 vote, the court ruled that motorists can be prosecuted for driving under the influence of drugs if they test positive for any trace of marijuana, including a metabolized remnant that experts say can stay in a person's system for weeks after the smoke. "They are automatically guilty even though they are no longer impaired by it," said Tim Beck, executive director of the Michigan chapter of the National Organization for the Reform of Marijuana Laws, which wants the drug legalized, taxed and regulated for adult use as alcohol is. "It's not based on common sense or justice."
Officers still need probable cause to believe a crime was being committed before they can request a blood test, but motorists who refuse could be found guilty of a civil infraction and lose their license. . .
Justice Michael Cavanagh called the ruling unconstitutionally vague. He cited expert testimony that noted the substance can be detected in a person's system for up to four weeks after being ingested -- long after its effects have worn off.
"Plainly, there is no rational reason to charge a person who passively inhaled marijuana smoke at a rock concert a month ago," Cavanagh wrote in a dissent joined by Justices Elizabeth Weaver and Marilyn Kelly. "Now, if a person has ever actively or passively ingested marijuana and drives, he drives not knowing if he is breaking the law, because if any amount of 11 carboxy-THC can be detected -- no matter when it was previously ingested -- he is committing a crime.
http://detnews.com/apps/pbcs.dll/article?AID=/20060623/METRO/606230342/1003