BOISE, Idaho – Investigators in Ada County Idaho say they’ve linked a previously-unsolved case of a man found dead in a church pew in 1982 to the infamous Tylenol poisonings that happened the same year.
The Ada County Sheriff’s Office announced the findings Wednesday morning.
The case started when a man was found dead by suicide in Boise’s Sacred Heart Catholic Church. He had no identification and was found with only a large sum of cash and anote signed Wm. L. Tooney. He also had a single engraved key.
His cause of death was cyanide poisoning.
Not able to identify him, investigators referred to it as a the Unknown Wanderer case.
Just a few months before, 1,700 miles away in Chicago, seven people in died after taking Tylenol laced with cyanide.
That case also remains unsolved.
The ‘key’ to the case
In 2019, the Ada County Sheriff’s Office Cold Case Detective Tim Cooper reopened the Unknown Wanderer case. He cross-referenced information with more than 17,000 missing persons records.
The key the dead man was carrying led investigators to a residential street in Jacksonville, Florida.
On that street once lived a man who disappeared in 1982. Family members and DNA confirmed the missing man was the man found dead in the Boise church. His name was Dr. Matthew Betkouski.
“Identifying the Unknown Wanderer opened an unexpected door,” Ada County Sheriff’s Office wrote in a news release. “Investigators found that Betkouski had worked in two drugstores during his undergraduate studies, giving him working knowledge of pharmacy operations. Those who knew him described a history of volatility, including a documented fascination with explosives.”
Detective Cooper identified people who knew Betkouski and reviewed thousands of pages of documents and letters.
“Among the details that emerged: colleagues recalled Betkouski discussing the idea of a ‘perfect crime’ and describing cyanide as a means to kill without detection,” the release said.
“Based on this body of evidence, ACSO has identified a possible connection between Betkouski and the 1982 Tylenol poisonings — an unsolved case that claimed seven lives in the Chicago area and remains one of the most significant unsolved crimes in U.S. history,” the release said. “ACSO has shared its findings with the Chicago Police Department.”
Ada County consulted with an expert who previously worked with the FBI on the Tylenol case. He presented the findings to forensic psychologists and psychiatrists who he said “showed overwhelming agreement” that Betkouski was a viable suspect for the Tylenol murders.
The case is now the subject of an upcoming Unsolved Mysteries documentary called Unmasking the Tylenol Killer.
Ada County investigators say the documentary will include additional evidence that has not yet been made public.
The documentary debuts October 9th on Roku.
“Our goal in partnering with Unsolved Mysteries was simple — we wanted more tips, and we wanted more evidence to come forward,
said Ada County Sheriff Matt Clifford. “Detective Cooper has done incredible work on this case, but there are still a lot of questions we don’t have answers to, and we’re hopeful this documentary helps us get there.”
The Ada County Sheriff’s Office is working with Chicago Police. They hope this information will allow them to develop new leads about this case and possibly others they don’t know about yet.
Investigators previously identified two suspects in the case. They even exhumed one corpse to look for a DNA match. Neither matched DNA collected on the Tylenol botles.
The FBI even requested DNA samples from Unabmomber Ted Kaczynski to see if he was connected.
It’s not clear in the announcement Wednesday if investigators have linked Betkouski’s DNA to the Tylenol bodies.
They want anyone with information about Betkouski to reach out at ACSOtips@adacounty.id.gov.
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