Marijuana users too high to drive for days, says study

Marijuana users should know they're not supposed to drive after getting high, but new research indicates that some users would be considered too high to drive for three days --even while they were sober.

Some defense attorney say that's reason to question the state DUI law.

"People have been wrongfully convicted, they’ve been wrongfully pressured into plea deals by DAs that believe they have the upper hand, and they do have the upper hand," said Denver Defense Attorney Sean McAllister.

But Tom Raynes, who represents Colorado District Attorneys, says Colorado’s limit of 5 nanograms of marijuana in the blood is only one piece of evidence.

"The likelihood of anybody first getting arrested and second getting convicted on 5 nanograms or higher, alone, is nearly impossible," he said.

The study is published in the journal Forensic Science International.