Defendant In 30-Year-Old Cold Case Sentenced To Life In Prison

Thomas David Cox

Maricopa County Attorney Rachel Mitchell has announced that Thomas David Cox, 60 has been sentenced to life in prison for the violent murder and sexual assault of two victims in 1989 and 1990.

“One of the most agonizing aspects of cold cases is the long uncertainty endured by victims and their families,” shared County Attorney Rachel Mitchell. “This defendant committed these offenses in such a cruel manner and then went on have a full life while the victim’s young life was halted. It’s only appropriate that this defendant spend the rest of his life in prison.”


On October 16, 1989, the Mesa Police Department conducted a welfare check on a 22-year-old who had not shown up for work. Upon entering the apartment, officers discovered the victim lying unresponsive on the bed. She suffered blunt force trauma to various part of her body and had been strangled to death with an electrical cord.

Over a year later, on November 13, 1990, Mesa Police responded to another sexual assault report in the same apartment complex. A stranger broke into a single mother’s home and sexually assaulted her. In both cases, police took DNA swabs and created a profile for the unknown male assailant.

On November 2, 2002, the Mesa Police Department Crime Lab found that the DNA in both cases matched, linking the crime scenes. The DNA was then compared to profiles of convicted offenders using the FBI’s national database of convicted offenders but yielded no results.

Approximately 20 years later, using advanced DNA testing funded by the Sexual Assault Kit Initiative (SAKI) Project*, Cox was identified as a suspect. His DNA matched samples collected from both crime scenes and his palm matched a print taken from the second victim’s apartment.

On February 2, Cox pled guilty to one count of first-degree premeditated murder, a Class One Dangerous Felony, and one count of aggravated assault, a Class Three Dangerous Felony. On March 12, he was sentenced to life with the possibility of release after 25 years for first-degree murder and to 10 years for aggravated assault. The sentences will run concurrently.