MCKINNEY, TX — A 52-year-old Denton man will never be eligible for parole after a Collin County jury sentenced him to 50 years in prison for the repeated sexual abuse of a severely autistic child. Marty Duwayne Griego was convicted on April 22, 2026, of Continuous Sexual Abuse of a Disabled Individual, a charge that carries a mandatory minimum of 25 years.
The Crimes and Investigation
The abuse occurred over the span of a year in Plano, Carrollton, and Corpus Christi, ending when the victim was 15 years old. Griego, who had an ongoing relationship with the victim's family, used that proximity to gain access to her.
The case came to light after Griego assaulted the victim in front of another child, who immediately notified authorities. Plano Police Detective Catherine Foreman led the subsequent investigation, which included a medical exam that produced DNA evidence directly linking Griego to the abuse. The victim also provided detailed accounts during a forensic interview at the Children's Advocacy Center of Collin County.
A Pattern of Predatory Behavior
During the punishment phase of the trial, prosecutors presented evidence that the autistic victim was not Griego's only target. The jury heard testimony that:
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Griego had sexually abused another child in a separate incident.
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An adult victim came forward to report a sexual assault by Griego after learning of his arrest.
Sentencing and Legal Impact
Under Texas law, the conviction of Continuous Sexual Abuse of a Disabled Individual is a first-degree felony. Because the jury assessed a 50-year sentence for this specific charge, Griego is legally barred from ever seeking parole.
Collin County District Attorney Greg Willis praised the verdict in a public statement:
“A serial predator who preyed on a severely disabled child will never walk free again. This 50-year, no-parole sentence delivers the justice our most vulnerable victims deserve.”
The trial was presided over by Judge Rayburn Nall. The prosecution team included Assistant Criminal District Attorneys Jean-Marie Anderson and Wendy Correa, assisted by Investigator Greg Bowers and Victim Assistance Coordinator Melissa White.
