DENVER (AP) -- A marijuana driving standard in Colorado could be moving closer to reality.

A special task force to study an impairment standard for drivers using medical marijuana is set deliver a report on Wednesday. State lawmakers tried and failed earlier this year to decide on a blood-content threshold that would allow prosecutors to charge drivers with a DUI. A proposal to set a 5-nanogram limit was rejected amid criticism that there is limited scientific evidence indicating a proper legal for THC, the psychoactive ingredient in marijuana.

A subcommittee of the Commission on Criminal and Juvenile Justice planned to hear the report on the driving-high study Wednesday. The commission could make recommendations to the Legislature for a new attempt at a pot DUI standard next year.

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