The greater availability of cannabis following legalization increases the likelihood that more drivers will drive drugged, rendering the determination of its effect on crashes a matter of vital public policy interest. For criminal justice agencies, this issue takes on increased importance, as drugged driving is a criminal offense. We examine the relative risk of cannabis (Delta-9-Tetrahydrocannabinols [hereafter THC]), alcohol, and the combination of the two, on fatal crashes in Washington state, using data from the Washington Coded Fatal Crash (WA-CFC) Files, which includes appended toxicology results. Findings indicate the presence of alcohol or the combination of alcohol and THC in the blood of a driver involved in a fatal crash is more likely to be associated with risky driving behaviors, fatal injuries, and death compared to THC alone.