Horton had shot up a house in Burien and wounded a 12-year-old boy. He then fled to his basement apartment in West Seattle. Witnesses reported that Horton said that he was going to shoot up his girlfriend's house then go home, have a gunfight with police, then kill himself.
Officers from King County and from Seattle arrived and told his girlfriend to leave the apartment. As she was leaving, Officer Halvorson pulled her out of the way and forced his way into the apartment. Horton fired at Halvorson and hit him in the head. Other officers returned fire, hitting Horton. Horton ran to a rear bedroom and turned his .22 caliber pistol on himself. Horton died at the scene and Halvorson died at the hospital.