The Colorado House gave its initial thumbs-up to a bill setting the cannabis driving limit at 5 nanograms of THC per milliliter of blood (5 ng/ml), reports The Associated Press.
Last year the pot DUI bill was rejected in the Senate after it was brought to light that a 5 ng/ml cut-off point is unsupported by science; the link between that blood THC level and driving impairment appears tenuous at best.
Last week, the Colorado House was once again poised to adopt the bad legislation, but the bill died as a result of a filibuster on a civil unions measure.
Sponsors of the marijuana DUI bill claim it is comparable to the blood-alcohol law for drivers, but opponents point out that blood THC levels -- especially at only 5 ng/ml -- don't correlate well with actual impairment.
The marijuana DUI bill faces one more vote in the House before going to the Colorado Senate.
For the complete bill, click here [PDF].