The Minnesota Supreme Court on Wednesday affirmed multiple decisions by lower courts that vacated the second-degree murder conviction of a former Stearns County man following false medical testimony given at trial.

Robert J. Kaiser, 41, was charged with murder following the death of his 2-month-old son, William, in 2014. The baby was taken to the hospital after having seizures, and imaging showed bleeding around his brain and retina.

A jury found Kaiser guilty in 2016 on two counts and a judge later sentenced him to 20 years in prison. But according to the Supreme Court opinion, written by Associate Justice Gordon Moore, the state's experts made false statements of medical fact to the jury that "proved crucial in establishing Kaiser's guilt."

Dr. Jeffrey Lynch, an ophthalmologist, examined William's eyes and observed macular schisis, for which he testified that abusive head trauma was the only cause. Later, during a nine-day evidentiary hearing, Lynch testified that if he did say trauma was the only cause of the eye ailment, that would have been incorrect.

The district court "gathered the facts necessary to conclude that the trial testimony was false," Moore wrote. "And the state's own witness in effect recanted his trial testimony."

After William was taken to the hospital, some doctors concluded his neurological decline was the result of abusive head trauma, documents state. While hospitalized he developed a fatal condition involving the disintegration of intestinal tissue, which resulted in his death. Kaiser was arrested within days.

"Given the lack of any bruising, laceration or other sign of impact to the infant's head, the state theorized Mr. Kaiser must have violently shaken William or slammed him into a soft surface," according to a release issued Wednesday by the Great North Innocence Project, an organization that works to free wrongfully convicted individuals. "At the trial, the state's medical witness relied heavily on medical imaging, insisting to the jury that there was no other explanation for the infant's neurological presentation."

The Great North Innocence Project started investigating Kaiser's case in 2020. A team of experts concluded the medical evidence did not support the trauma diagnosis and instead identified a nontraumatic medical cause for his condition: blood clots in his brain veins known as cerebral venous thrombosis, a "serious medical condition that causes many of the same symptoms often attributed to [abusive head trauma]."

Kaiser filed for postconviction relief, which the district court granted in April 2022 after finding his conviction rested on false evidence. That decision was affirmed by the Minnesota Court of Appeals in February 2023 and affirmed Wednesday by the Supreme Court.

"We recognize the tragedy that comes with the death of a child and the pain a surviving family and community endure in experiencing such an unthinkable loss," Moore wrote in his opinion. "We do not affirm the reversal of a murder conviction lightly, and we make our decision realizing a new trial will cause renewed pain for William's family."

The district court could conduct a new trial in Kaiser's case. Stearns County Attorney Janelle Kendall said Wednesday her office will be looking at options on how to proceed.