July 23rd, 2025 Local News
Jefferson County, Mo. (KFMO) - After nearly 30 years, the Jefferson County Sheriff’s Office has positively identified a previously unknown man found in the Mississippi River near Festus in 1994.
Sheriff Dave Marshak announced that the man, buried in 1995 as a John Doe in a north St. Louis County cemetery, has now been identified as Benny Leo Olson of Illinois.
Olson’s identity was confirmed following the exhumation of his body last fall and a detailed investigation involving forensic science, law enforcement, and genealogical experts.
Detective Lee Morris and Analyst Heather Missey from the Sheriff’s Office partnered with Kathleen Diebold Hargrave of the Regional Medical Examiner’s Office, forensic genetic genealogist Alyssa Feller, Dr. Lindsay Trammell of the St. Louis County Medical Examiner’s Office, and Captain Jerry Endicott from the Madison County Sheriff’s Office.
The team worked together to extract and sequence Olson’s DNA. Investigators then scoured records and genetic databases to make a match.
“I am honored to have assisted the Jefferson County Sheriff's Office in identifying Mr. Olson after so many years,” said Feller. “This case resolution is a testament to the power of investigative genetic genealogy to give John and Jane Does their names back and provide answers to family.”
Madison County Sheriff Jeff Connor added, “This is one more example of how law enforcement across our nation continues to work hand in hand toward solving crimes and keeping our citizens safe.”
“This case highlights the remarkable impact of teamwork across forensic science, law enforcement, and genetic genealogy,” said Diebold Hargrave. “We’re deeply grateful for all the professionals who made this possible.”
