"We are doing everything we can to maintain the integrity of this case and have a solid case to present to the Salt Lake County District Attorney’s Office for prosecution," Roberts said. Earlier, the chief described the shooting as an "ambush."
Gill said officers from the Unified Police Department and the Draper Police Department are working with attorneys from his office to conduct an "expeditious and thorough" probe of the events that resulted in the sergeant's death. His homicide team attorneys have also been writing warrants as part of the case.
"We're trying to gather as much information about what happened, who was involved. As they finish their investigation, we will work toward accountability," Gill said Monday.
Gill said the events were "an absolute tragedy. From our perspective, our heart goes out to the officer's family and to his community."
Johnson is the first Draper police officer to killed in the line of duty. Gill said his death illustrates the dangers police encounter on a daily basis.
"This young man was a professional who was well-respected and well-loved in his community. He was well-known in the community, out there doing the job he loved to do and doing it honorably and professionally. To be struck down in this sort of way is just an absolute tragedy and a loss for that man's family, the community and everyone," he said.
Johnson is survived by his wife and a 7-year-old son.
Anyone who may have seen the silver Volvo Saturday night or Sunday morning is asked to call Unified police at 801-743-7000.
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