PHOENIX, AZ — Maricopa County Attorney Rachel Mitchell announced that Thomas Samuel Wallace (DOB 02/1964) has been sentenced to natural life in prison for the brutal murder of 79-year-old Kenneth Maynard Petersonin 2022.
The disturbing case unfolded after Phoenix Police received multiple welfare check requests for Peterson, who had not been seen or heard from for several weeks. Upon entering his residence, officers discovered Peterson’s decomposed and dismembered remains concealed in trash bags.
The investigation revealed that Wallace had been driving the victim’s truck and had stolen several of his belongings, which he later used or sold for personal gain. Surveillance footage, pawn shop records, and digital forensic evidencerecovered from cell phones helped tie Wallace to the crime. He was ultimately arrested while behind the wheel of Peterson’s vehicle.
Following a thorough prosecution, Wallace was convicted of the following charges:
First-Degree Murder (Class 1 Felony)
Unlawful Use of Means of Transportation (Class 5 Felony)
Two Counts of Trafficking in Stolen Property (Class 3 Felony)
Abandonment or Concealment of a Dead Body (Class 5 Felony)
“It is astonishing to me that this defendant thought he could kill a man, drive his truck, and profit from his belongings yet still think he wouldn’t be caught,” said County Attorney Rachel Mitchell. “That will never be the case in Maricopa County—at least not on my watch. Law enforcement will catch you, and my office will prosecute you. It’s just that simple.”
Wallace will now spend the rest of his life in prison without the possibility of parole.
