Samples of hemp sit on a table in the conference room at Andrew Ross' office in Denver on Friday, March 22, 2019. Ross, a Marine who served in Afghanistan and Iraq, is facing 18 years to life in Oklahoma if he is convicted after he was arrested in January while providing security for a load of state-certified hemp from Kentucky. Federal legalization for hemp has created a quandary for police as authorities lack the technology to distinguish marijuana from agricultural hemp at a roadside stop.