The Colorado Daily reported this week that the Colorado State Patrol has begun ticketing drivers who drive in the left lane when they’re not passing.

Officers are enforcing the passing lane law passed by the state Legislature in 2004. The law authorizes police to ticket offenders for using the farthest left lane on 65-mph or higher highways for anything other than passing or exiting left. Breaking the law can result in a $35 ticket, $6.20 surcharge and three points on the offender's license.
Officers have been issuing warning notices since July 1, but serious enforcement began Jan. 1. The law is in effect at all times on all multi-lane 65 mph or higher roads, with the only exception being "rush hour," or other times of day when all lanes are in use.
The law was passed to facilitate traffic flow and help deter “road rage.”