How high is too high? 5 years after legalization, Colorado struggles to test marijuana impairment for drivers

STEAMBOAT SPRINGS — In 2014, when recreational marijuana became legal in Colorado, Matt Karzen, an assistant district attorney in Routt County at the time, noticed a lot of criminal cases coming to his office involving drivers … Continue reading How high is too high? 5 years after legalization, Colorado struggles to test marijuana impairment for drivers