Denver Judge Overturns 2000 Infant Murder Conviction After Pneumonia Evidence
A Denver judge overturned a 2000 infant murder conviction after new evidence suggested pneumonia caused the baby's death. The decision, handed down this year in Denver, found that medical evidence about a severe pneumonia episode undermined the scientific basis for the original verdict. Prosecutors had relied on forensic testimony at trial to say the infant's death was intentional, but the judge said the new findings cast doubt on that conclusion.
Earlier coverage and the original trial framed the death as a homicide based on the available forensic interpretations, which supported the conviction in 2000. Newer reporting, including ABC News' recent account, focused on the pneumonia evidence and expert reanalysis, shifting the story toward medical explanations and legal doubt. That shift has prompted renewed scrutiny of how infant deaths are evaluated and of the forensic testimony that informed similar prosecutions.
đ Key Facts
- Judge Andrew Luxen in Denver overturned Stephen Martinez's first-degree murder conviction and ordered his release on April 21, 2026.
- Martinez was convicted in 2000 and sentenced to life for the 1998 death of 4-month-old Heather Mares, his then-girlfriend's daughter.
- New defense medical evidence indicated the baby died of pneumonia, leading prosecutors to concede they could not prove guilt beyond a reasonable doubt.
- The Denver District Attorney's Office did not oppose the motion to vacate and the case was dismissed despite the family's objections.
- Martinez had been charged under a then-new Colorado statute allowing first-degree murder charges in certain child-death cases.
đ° Source Timeline (1)
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