Defense attorneys: Testing for drugs in DUI cases may be netting the wrong people

It's unclear how many DUI cases involve drugs versus alcohol or some combination of both. TBI director Mark Gwyn estimated in 2014 that agents retest blood samples for drugs in 35 to 40 percent of impairment cases statewide. In 2016, 23,130 people were arrested statewide for DUI, with at least 627 of ...