When Ed Wood's 33-year-old son Brian was killed in a devastating crash involving a vehicle whose occupants had used marijuana, methamphetamine, and heroin, his life changed forever. Ed devoted the next 16 years to investigating drug-impaired driving, eventually presenting his research in federal proceedings concerning marijuana's proposed reclassification to Schedule III. In this powerful conversation with Joanie Sigal, Ed explains why THC impairment is difficult to measure, the dangers of combining drugs, and the serious challenges facing law enforcement and policymakers. A father's personal tragedy has become a mission to protect other families.

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