CADDO COUNTY UNSOLVED: THE MURDER OF DIANE GAIL MINTON SHENOLD

ANADARKO — This week we're covering the case of Diane Gail Minton Shenold for our Unsolved Caddo County series. More than 35 years have passed since Diane was killed, and her case remains unsolved to this day. Even after all this time, her children deserve answers, and Diane deserves justice.

Today, we remember Diane and honor her memory. That being said, let's start with a little background first so you can know who Diane was as a person.

According to Find A Grave and other publicly available sources, Diane was born on November 9th, 1953, in Nowata, Oklahoma, to Helen and Rube Minton. A few years later, her family reportedly moved to Stillwater, where she attended and graduated from Stillwater High School. After high school, Diane attended Oklahoma State University and later earned her degree. We're unsure of the exact timeline here, but it has been reported that Diane later married Lance Shenold, and the couple had two children together. Reports also indicate that the marriage later ended in divorce.

Like many people, Diane continued moving forward with her life. At the time of her death, she was living in Anadarko and working for Western Farmers. By all accounts, she was focused on her family, her children, and building her future. Tragically, that future was cut short on July 10th, 1989. Diane was found deceased inside her Anadarko home at just 35 years old. According to reports, investigators later determined that she had been smothered with a pillow.

Over the course of the investigation, authorities reportedly conducted around 200 interviews and pursued numerous leads. According to published reports, investigators ultimately narrowed their focus to one individual.

According to archived news reports and court records, Timothy Bates was identified by investigators as a suspect in Diane's homicide. Bates was subsequently arrested and charged in connection with the case. It is important to note that a charge is merely an allegation, and Mr. Bates is presumed innocent unless proven guilty in a court of law.

According to reporting by The Oklahoman, the case was tried three separate times. The first trial was held in October of 1990 and ended in a mistrial after the jury was unable to reach a verdict. Reports indicate the jury was deadlocked 8-4 in favor of conviction. A second trial followed in December of 1990, but it also ended in a mistrial after a juror reportedly suffered an injury during deliberations.

The case was tried for a third and final time in October of 1992, nearly two years after the second trial concluded. According to The Oklahoman, the jury was made up of six men and six women who deliberated for about an hour before returning a not guilty verdict on Bates' first-degree murder charge. As a result of that acquittal, Mr. Bates cannot be retried for Diane's homicide. Because Bates was acquitted, no court has found him guilty in connection with Diane's homicide.

And years later, Diane's case would unexpectedly cross paths with another Oklahoma cold case.

In 2013, News 9 reported that investigators with the Norman Police Department were able to obtain a DNA sample from Bates. However, the warrant used to obtain Bates' DNA was not originally connected to Diane's case.

Instead, it stemmed from another unsolved homicide investigation involving Dorothy Estes. Dorothy was found strangled inside her trailer home near Lexington on May 8th, 1989, just a few months before Diane's death. According to media reports, investigators reportedly explored whether Bates could be connected to Dorothy's murder as well. However, based on the information we were able to locate, we found no records indicating that Bates was ever convicted or found guilty in connection with Dorothy Estes' death. As of today, Dorothy's homicide also remains unsolved.

Although the DNA was collected during the Estes investigation, reports indicate the sample later became relevant to investigators reviewing Diane's case. However, the significance and interpretation of that evidence was disputed during the legal proceedings, and Bates was ultimately acquitted of the charge against him. As we previously noted, Diane's murder remains officially unsolved.

More than 35 years have passed since Diane was killed, yet the questions surrounding her death have never been fully answered. Despite decades of investigation and multiple trials, no one has ever been held criminally responsible for Diane's death. And sadly, we're not sure justice will ever be served for Diane and her family. But, we will continue to remember Diane, and ensure that her story is not forgotten.

If you have any information regarding the murder of Diane Gail Shenold, please contact the Oklahoma State Bureau of Investigation at 800-522-8017.

Important Note: This article is based on publicly available news reports, court records, archival sources, and historical reporting. Any references to individuals who were investigated, arrested, charged, or identified as suspects are included solely for historical and factual context. An arrest, charge, or accusation is not evidence of guilt. Timothy Bates was acquitted of the charge brought against him in Diane Shenold's homicide, and the case remains officially unsolved.