Johnny Paul Penry was born on May 5, 1956, in Texas. He grew up in an abusive household, where he suffered severe physical abuse that reportedly led to lifelong intellectual disabilities. His IQ was estimated between 51 and 63, classifying him as intellectually disabled. His mother allegedly beat him, locked him in closets, and denied him basic education, leaving him with minimal reading and writing skills.

Penry had a history of violent behavior and criminal activity before the murder that would later define his life. At the time of the crime, he was on parole for a 1977 rape conviction. Despite his intellectual disabilities, he was considered legally competent to stand trial and was released on parole in early 1979.

On October 25, 1979, in Livingston, Texas, Johnny Paul Penry entered the home of 22-year-old Pamela Moseley Carpenter, the sister of former Washington Redskins kicker Mark Moseley. Carpenter was alone in her house when Penry broke in.

Penry brutally raped and stabbed Pamela multiple times with a pair of scissors. She suffered severe wounds and later died from her injuries. Before leaving the crime scene, Penry attempted to stage the house to cover up his involvement. However, he was arrested later that day based on evidence linking him to the attack.

Following his arrest, Penry confessed to the crime but later claimed he did not fully understand his actions due to his mental state. His trial became one of the most controversial death penalty cases in U.S. history because of his intellectual disability.

Despite multiple trials and appeals, including landmark Supreme Court cases (Penry v. Lynaugh, 1989, and Penry v. Johnson, 2001), Penry was resentenced to death multiple times before finally accepting a plea deal in 2008. This resulted in a life sentence without parole, ending a legal battle that lasted nearly 30 years.