A marijuana blood limit for drivers has failed in Colorado for the fourth time. This year's stoned-driving bill was expected to pass because pot use is expected to increase because of legalization for adults over 21. Also, the bill would have given defendants a chance to argue they were sober despite blood levels above the legal limit. The measure failed 1-4 Monday in a Senate committee. It had already passed the House. Driving under the influence of any drug is already illegal in Colorado.

See more at CBS Local News