Meanwhile, Walker's girlfriend, Traci Vaillancourt, 34, had been upgraded from critical to fair condition a relative says Vaillancourt was shot in the back and she has talked with investigators.
However, Hoyal would not detail the content of those interviews, which conceivably could bear on Walker's possible motive in allegedly ambushing Johnson as he sat in his patrol unit.
"This investigation is still ongoing," Hoyal said. "Detectives have been able to speak with Vaillancourt, [but] the details of those conversations will not be released."
However, Hoyal did indicate that there was nothing learned thus far that diminished investigators' belief that "Walker is the suspect in this case and Vaillancourt is a victim."
Johnson had stopped to investigate after seeing Walker's Volvo which he and Vaillancourt had been living out of parked at an odd angle on a street. After being shot, Johnson drove a short distance before crashing.
According to a relative who asked not to be identified over safety concerns, Walker purchased the Volvo from an old friend of his. The relative said the money for the car, as well as for hotels the couple lived in for years, came from Vaillancourt's Social Security Disability Insurance payments, which she received as a result of a debilitating blood disorder. At some point recently, the relative added, Vaillancourt also received a check for about $40,000 in back payments.
Walker also was not violent in his past relationships and was "not a cop hater," the relative said.
The shooting occurred about 6 a.m., when officers from the graveyard shift return to the station to clock out, said Maridene Hancock, city spokeswoman. Johnson was mere blocks away.
Funeral services for Johnson, who left behind a wife and young son, are set for 11 a.m. Friday at the Maverik Center, 3200 S. Decker Lake Drive (2200 West) in West Valley City. A public viewing was held there Thursday.
The ceremonies originally were planned to be held at the Salt Palace Convention Center, but they were moved due to other large events in downtown Salt Lake City. Salt Lake Comic Con, which has sold 30,000 tickets, and the Greek Festival are planned for Friday.
Johnson's interment will be at Larkin Sunset Gardens, 1950 E. Dimple Dell Road (10600 South) in Sandy.