Mary Ann Green was 59 years old when her life was violently taken on September 27, 1987. She was found stabbed to death inside her mobile home at Spring Creek Mobile Park along Highway 23 South in Oskaloosa. The case fell under the jurisdiction of the Mahaska County Sheriff’s Office and quickly became one of the community’s most troubling crimes.
Investigators soon focused on two suspects: Green’s stepson, Richard Lee Green, and his acquaintance, David Kelly Yant. Both men were charged with first-degree murder, and what followed was a long and complicated legal process. Their first trial, held in Mahaska County, ended with a hung jury. A second trial in Polk County also failed to reach a verdict, resulting in another deadlock. A third and final trial was later moved to Washington County, where a jury ultimately acquitted both men on March 2, 1989.
For many, an acquittal can leave lingering questions. Those familiar with the criminal justice system understand that a “not guilty” verdict does not always mean the truth is fully resolved. Jurors do not always hear every piece of evidence, often due to legal rules governing what can be presented in court, and verdicts are shaped not only by facts but also by legal strategy and courtroom presentation.
Iowa Cold Cases later reached out to both the Oskaloosa Police Department and the Mahaska County Sheriff’s Office to ask about the status of the case. According to Mahaska County Sheriff Paul R. DeGeest, the murder of Mary Ann Green is considered unsolved “by lawful terms.” No active investigation is underway, and authorities have stated there will be no further investigation into her death.
Mary Ann Green was laid to rest at Forest Cemetery in Oskaloosa. Nearly four decades later, her case remains a quiet but painful reminder of a life lost and a homicide that, legally, has never been resolved.
