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Crime News Violent Minds: Killers on Tape

Violent Minds: Killers On Tape To Explore Child Killer Manuel Cortez's Crimes

Two girls went to play tennis together and never returned. Manuel Cortez is the reason.

By Cydney Contreras

Clinical psychologist Al Carlisle spent 50 years interviewing and studying serial killers. Manuel Cortez fit squarely into his specialized field of research. 

How to Watch

Watch Violent Minds: Killers on Tape on Peacock. Catch up on the Oxygen App.



The Oxygen series Violent Minds: Killers On Tape features the late Dr. Carlisle’s never-before-heard interviews and investigations into killers. There’s hope that fresh insights may emerge about past infamous cases.

Like the two subjects in the title of Carlisle’s book, Mind of the Devil: The Cases of Arthur Gary Bishop and Westley Allan Dodd, Cortez was a child murderer.

RELATED: ‘I Killed Them All’: Serial Killer Arthur Gary Bishop Chillingly Describes How He Lured And Killed His Victims

On December 27, 1979, in Ashland, Oregon, 11-year-old friends Rachel Isser and Deanna Jackman went to play tennis at a park near Southern Oregon State College, according to the Associated Press. They never came home.

Isser’s naked body was found in the press box at the college’s football field. A day later, police found Jackman by a gravel pit at the border of Ashland.
Autopsies revealed the girls had been suffocated and “molested sexually,” according to the AP report. “We’ve got the city’s biggest detective force ever working on this,’’ the city’s police chief said in the report. 

The investigation eventually led to Cortez, who was born in Texas and moved with his family to the San Gabriel Valley, California as a child.

Manny Cortez, featured in Violent Minds: Killers on Tape 108

In 1975, a then-19-year-old Cortez was put on probation for attempted kidnapping, after he tried to abduct a 17-year-old girl, according to a 1993 Los Angeles Times report. 

The following year, he was arrested in two separate incidents for the kidnapping, rape and attempted rape of two teen-age girls. The charges were later dismissed.

In 1977, Cortez kidnapped a 16-year-old girl who escaped and identified him as a suspect, which caused him to flee to Oregon, per the Los Angeles Times report.

In 1980, Cortez, who prosecutors labeled a sexual sadist, was tried first in the Jackman case, but that trial ended in a hung jury, UPI reported. The two cases were merged for a single trial that ended with his conviction.

In 1982, Cortez pleaded guilty to the 1977 kidnapping, according to the Los Angeles Times. He emerged as a suspect in other unsolved homicides.

Where is Cortez now and what were Carlisle’s insights and observations about the killer? To find out, watch Violent Minds: Killers On Tape, airing Sundays on Oxygen.