[Joy Bergmann wrote a November 2000 Reader story called “A Bitter Pill,” about the unsolved Tylenol murders. Here’s a follow-up.]

No one has ever been charged as the perpetrator of the 1982 Tylenol murders in which seven Chicago-area residents died after consuming cyanide-laced Extra Strength Tylenol capsules.

No one has ever been charged as the perpetrator of the 1986 Tylenol murder of Diane Elsroth, who died after consuming cyanide-laced Extra Strength Tylenol capsules purchased in Westchester County, New York, despite the triple-sealed, tamper-resistant packaging instituted following the 1982 deaths.

In a new self-published book, The Tylenol Mafia, author Scott Bartz says he knows why these crimes continue to confound investigators: authorities were steered toward an erroneous madman-in-the-drug-store theory of the crime. A crime Bartz believes never occurred in retail stores. He says the evidence shows the culprit put the poisoned capsules into bottles somewhere along the repackaging and distribution links in Tylenol’s supply chain. A distribution system the police did not understand and the media did not investigate. A multiparty, multifaceted distribution system closely guarded by the makers of Tylenol and Bartz’s former employer, Johnson & Johnson.