Boise police arrest driver who allegedly hit, killed pedestrian on State Street
Boise police arrested a 49-year-old, allegedly drunken driver after law enforcement said he drove off of State Street and onto a sidewalk Sunday night, striking and killing a pedestrian.
William Sweet, of Caldwell, was traveling in his white 2007 Lexus sedan eastbound on State Street near 23rd Street when he drove his vehicle off the road, according to a probable cause affidavit obtained by the Idaho Statesman. He continued driving onto grass and a sidewalk along State Street when his vehicle hit a man and crashed into someone’s front lawn, where he struck a large cement sign, the affidavit said.
Numerous bystanders called 911 to report the collision, and one man saw Sweet crawling out of the passenger side of his vehicle, according to the affidavit. Sweet had “indicators of impairment,” the affidavit said.
The pedestrian, who hasn’t been identified, died from his injuries at the scene, according to a news release from the Boise Police Department. The Ada County Coroner’s Office will release the victim’s identity once his next of kin has been notified.
In recent months, the Treasure Valley has seen a string of fatal pedestrian-vehicle crashes.
In September, a 58-year-old woman was killed in a parking lot near The Village in Meridian, and a 45-year-old man died from “complications of multiple blunt force injuries” in October a week after he was struck by a vehicle in Caldwell. More recently, an 8-year-old girl’s death, after she was struck by a pickup truck while crossing Harrison Boulevard, prompted reduced speed limits. And, in December, a 78-year-old man died after he was struck by a pickup truck while crossing a street in Meridian.
Sweet was taken to Saint Alphonsus Regional Medical Center for a reported head injury, where Boise Police Officer Hayli Talbot conducted a DUI investigation, the affidavit said. Talbot wrote in the affidavit that Sweet smelled strongly of alcohol and had slurred speech, bloodshot glassy eyes and impaired memory.
Talbot administered a breath alcohol concentration test, which provided three slightly varying results all showing Sweet was over the legal limit, she wrote in the affidavit. One of the results of .232% put him at nearly three times the legal limit of .08%.
Sweet was initially arrested on suspicion of felony aggravated DUI, but a criminal complaint filed by the Ada County Prosecutor’s Office shows he was charged with vehicular manslaughter.
He’s being held at the Ada County Jail on a $350,000 bond, according to online court and jail records.
This story was originally published January 5, 2026 at 2:09 PM.
