Smith said he would release further details only after receiving an official autopsy report from the state Medical Examiner's Office. Smith did confirm that the autopsy had been done on Monday, but he did not say when he expected to release the findings.
Police were called to the home in the 100 block of 4th Street about 2:30 a.m. Sunday on a report of domestic violence. When the officers were inside the home investigating, Collier allegedly fired at them, and they returned fire while retreating. Collier then barricaded himself inside, police said.
The SWAT team was called when Collier refused demands to come out and surrender. Police later entered the home and found him dead inside.
The officers involved have been placed on paid administrative leave pending review of the incident.
On Tuesday, no one answered the door of the home, in which there were bullet holes in street-facing windows.
A woman who keeps to herself lives at the home, and has two children, ages 4 and 6 months, according to a neighbor.
Utah court records show Collier had appeared before judges numerous times going back to 1995 on a variety of minor alcohol- and traffic-related offenses. However, in 1998 he pleaded guilty to misdemeanor cohabitant abuse, and was again accused of domestic violence in a 2009 petition for a protective order.