The murder of a wealthy Mahaska County widow in 1987 shocked southeast Iowa and sparked a years-long investigation centered on greed, inheritance money, and allegations of a murder-for-hire plot.
Mary Ann Green, a 59-year-old widow living at Spring Creek Mobile Park south of Oskaloosa, was found stabbed to death inside her home on September 27, 1987. Investigators described the attack as violent and deeply personal.
Authorities said Green suffered multiple stab wounds and severe injuries to her hands while attempting to defend herself. In one of the case’s most haunting details, investigators reported that Green used her own blood to write the letter “N” on a mirror before she died.
The killing immediately puzzled both investigators and members of Green’s extended family. Friends described her as quiet and modest, and many people outside her inner circle were unaware she had recently inherited a large estate following the death of her husband, Herman Green, earlier that year.
Herman Green had operated a successful backhoe business in Oskaloosa for years. After his death in June 1987, Mary Ann inherited an estate estimated between $700,000 and nearly $1 million.
According to court records and investigators, her will divided the inheritance equally among her nephew and her five stepsons, with each expected to receive a substantial payout.
Mahaska County Sheriff Joe Beal publicly stated investigators believed money was the motive behind the homicide. Attention soon focused on one of Herman Green’s sons, Richard Lee Green, and an acquaintance from California, David Kelly Yant.
In November 1987, prosecutors charged both men with first-degree murder. Authorities alleged Richard Green arranged the killing and that Yant carried it out.
Investigators pointed to motel records showing a man resembling Yant stayed in Oskaloosa around the time of the murder. Prosecutors also cited telephone records and evidence that money had been wired to Yant shortly before the killing.
The case drew statewide attention and led to three separate murder trials over the next two years.
During the first trial in 1988, prosecutors presented evidence they believed connected the pair to the homicide, while defense attorneys challenged the handling of evidence and argued investigators had failed to prove the case beyond a reasonable doubt. The jury was unable to reach a verdict.
A second trial later that year also ended in a deadlocked jury after weeks of testimony.
Despite two mistrials, then-Iowa Attorney General Tom Miller ordered prosecutors to pursue the case a third time, saying most jurors in the second trial reportedly favored conviction.
The third trial was moved to Washington County in 1989. After deliberations, jurors found both Richard Green and David Yant not guilty.
Following the acquittal, Richard Green returned to California and later received his portion of Mary Ann Green’s estate. Reports at the time indicated much of the inheritance was used to reimburse the state for legal defense costs.
Although the criminal case ended in acquittals, the murder of Mary Ann Green remains one of the most disturbing and widely remembered homicide cases in Mahaska County history.
Please note: Information in this article is based on historical reporting and court proceedings. Credit should be given to Nancy Bowers and Iowa Unsolved Murders: Historic Cases as the original source material.
