Joshua Sinclair Owens, 35, who the Harris County District Attorney's Office described as a repeat offender, pleaded guilty to murder for the strangulation June 2008 death of 48-year-old Marsha Lynn Mitchell.
According to authorities, Owens sexually assaulted Mitchell before killing her and dumping her body behind a construction site in Houston's south side. Her case went cold for more than 15 years before detectives used DNA evidence tying him to the crime.
The DA's office added that while he awaited trial, Owens masterminded a scheme to sell drugs to other inmates, accumulating $30,000 in his jail commissary. On Wednesday, he pleaded guilty to engaging in an organized criminal activity.
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On top of that, authorities said Owens also pleaded guilty to aggravated assault of a family member for assaulting his girlfriend in 2022.
He was sentenced to 50 years for each conviction. His sentences will run concurrently, according to records.