Story perspectives

DNA and key link revive Tylenol killer case in Idaho

By Drooid · Sep 25, 2026, 6:36 PM UTC · How we work

Summary

Roku Premieres Tylenol Killer

Roku will premiere “Unmasking the Tylenol Killer” documentary on Oct. 9.
Detective Tim Cooper reopened the cold case in 2019, sparking the identification effort.
FBI and Arlington Heights police said the investigation remains open and unsubstantiated.
Jeremy Margolis, former Illinois State Police director, dismissed the Idaho link as utter nonsense.
An engraved key found on the victim’s body led investigators to a Jacksonville, Florida property.

Summary

Idaho Investigators Identify Betkouski

Idaho investigators identified Wanderer as Dr. Mathew Francis Betkouski on September 23, 2026.
Detectives traced a key to Jacksonville and matched DNA to his brother.
Betkouski died cyanide suicide on December 4, 1982, at Boise’s Sacred Heart Church, leaving $1,900.
Dr. Park Dietz said Betkouski, a chemist with a 1974 brain injury, was Tylenol suspect.
Ada County officials sent evidence to Chicago investigators but have not named Betkouski a suspect.

History

Historical Context

In 1982 the Chicago Tylenol murders prompted the FDA, led by Commissioner Arthur Hayes, to require tamper-evident packaging, forcing Johnson & Johnson to add foil seals and cutting drug-tampering incidents by about 90 % within two years. The 2026 Idaho investigation by detectives headed by Tim Cooper, which linked DNA to Dr. Mathew Francis Betkouski, shows how those regulatory reforms still drive multi-state forensic cooperation.

1 of 3

Roku Premieres Tylenol Killer

Roku will premiere “Unmasking the Tylenol Killer” documentary on Oct. 9.
Detective Tim Cooper reopened the cold case in 2019, sparking the identification effort.
FBI and Arlington Heights police said the investigation remains open and unsubstantiated.
Jeremy Margolis, former Illinois State Police director, dismissed the Idaho link as utter nonsense.
An engraved key found on the victim’s body led investigators to a Jacksonville, Florida property.

1 / 3