A law that would have meant a DUI conviction if you had trace amounts of THC in your blood failed in the California Legislature last week.

AB 2500, by Assemblyman Jim Frazier, would have meant you could be convicted of driving under the influence if any amount of THC metabolites were found in your blood stream.

But the legislation was later amended to reflect a 2 ng/mL (nanograms-per-milliliter) blood limit, which is much lower than the 5-nanogram limit being discussed by many prosecutors and lawmakers.

Medical marijuana advocates argue that no limit is really fair because the metabolites can stay in your system for days. They’ve said that marijuana DUI limits will ensnare users who might have medicated a day or two before driving, but who are not high.

NORML says:

Because THC remains detectable in the bloodstream for hours or days after use, well after deleterious effects have faded, the bill would make marijuana users liable for DUI regardless of whether they were actually impaired at the time.

The bill was defeated in the Assembly Public Safety Committee 4-2. One of the no votes came from a longtime advocate for sensible cannabis policy, Assemblyman Tom Ammiano.

The proposed law also targeted cocaine, meth, heroin, morphine, and other drugs. NORML says such legislation is not necessary when it comes to cannabis, though:

Even while marijuana usage has been increasing over the past decade, accident rates and DUI arrests in California have been declining. Some experts speculate that this may be because drivers are substituting marijuana for alcohol. In any case, the evidence seems clear that marijuana isn’t causing an epidemic of accidents.

Editor's note: This article originally published on the 420 Times on Friday, May 2, 2014.

Photo Credit: The Kansas City Star