Bass said investigators tied Spencer to the slaying of 84-year-old Shirley Sharp by studying security footage of a traffic stop on the day of the killing. Investigators also had "an enormous response" from the public after the story made headlines, though Bass did not go into detail about specific tips police received.
No formal charges had been filed against Spencer in Sharp's death as of Friday afternoon. Bass would only say the case was still under investigation.
Police initially had sought a transient panhandler in the death, but later cleared him, saying he only resembled a man seen driving Sharp's stolen car hours before police and firefighters found her body inside her burning home at 20 E. Winchester St. (6400 South).
A Utah Transit Authority video security camera captured images of a middle-aged, bearded suspect during a UTA police stop. The man, who had driven in a restricted bus lane, briefly exited the vehicle before driving away before he could be questioned.
The UTA officer wrote down the vehicle's license plate number and traced it to a Buick LeSabre registered to Sharp. Police were dispatched to her home only to see smoke pouring from the small, red-brick residence. They called firefighters to the scene, who doused the flames and discovered Sharp's body inside.
An autopsy determined the woman, who lived alone, had died from blunt force trauma to the head.
While the specific nature of the probation violation allegedly committed by Spencer was sealed, federal court records do show that he had pleaded guilty in April 2005 to drug and firearms charges. He received prison sentences of 92 months on the drug charge and 72 months on the firearm violation, which were to run concurrently.
U.S. District Judge Dale A. Kimball, who handled Spencer's drug case, asked that Spencer do his time at a federal prison in Fort Worth, Texas, so that he could receive mental health and drug abuse treatment. The Federal Bureau of Prisons wasn't able to accommodate that request because Spencer was considered a medium security offender; he was sent to a prison in Beaumont, Texas.
Kimball also ordered that he be supervised for 48 months after finishing his prison term.
Spencer transitioned to a re-entry program shortly before his scheduled April 6, 2011, release from prison. But his probation officer said Spencer did not have a place to live or a job and asked that he be allowed to remain in the center for up to six months while he saved some money and found appropriate housing.
Spencer was unsuccessfully discharged from a GEO Care Residential Re-Entry Program in Salt Lake City on May 24, 2011, after he committed an unspecified theft.
He was re-arrested and sentenced to an additional eight months in prison, which Spencer began serving at the federal prison in Florence, Colo., on July 20, 2011. Upon his release in February 2012, he was to remain under supervision for another 48 months.
In Utah, 3rd District Court records show Spencer has a criminal record going back to 1997, which includes convictions for forgery, theft, credit card fraud and possession of a controlled substance. In 2011, Spencer was charged with stealing credit cards from a Salt Lake City housemate and using them to withdraw $400 from ATMs, according to charging documents.
Tribune reporter Jim Dalrymple II contributed to this story.