Basically unenforceable with the current situation on the front range...
Source: https://codes.findlaw.com/co/title-4...42-4-1013.htmlA person shall not drive a motor vehicle in the passing lane of a highway if the speed limit is sixty-five miles per hour or more unless such person is passing other motor vehicles that are in a nonpassing lane or turning left, or unless the volume of traffic does not permit the motor vehicle to safely merge into a nonpassing lane.