Everett police say Shawn K. Wilburn was on SR-529 near Steamboat Slough when his Ford Explorer hit a barrier and rolled over, ending up back on its wheels.
During the roll, Wilburn's passenger, 26-year-old Kyle Finch of Mukilteo, was thrown from the Explorer. He died at the scene.
Police say instead of stopping, Wilburn continued driving the damaged SUV for nearly half a mile before crashing into a forested median.
Officers and medics arrived a short time later and transported Wilburn to Providence Medical Center for medical assessment.
Witnesses told officers Wilburn was driving erratically just before the crash, and detectives believe he was under the influence of drugs or alcohol.
Police arrested Wilburn and booked him into Snohomish County Jail on suspicion of vehicular homicide and hit-and-run.