In 1991, a Florida jury convicted Trepal, a sophisticated chemist and Mensa member, of murdering his neighbor Peggy Carr and attempting to murder six other members of Carr's family. Trepal poisoned the victims by adding the toxic element thallium to bottles of Coca-Cola in the Carrs' home.
Trepal’s trial lasted a month, with more than 70 witnesses together providing overwhelming evidence of Trepal’s guilt. For example, several independent witnesses chronicled Trepal’s long-running conflicts with and animosity toward the Carr family. Evidence established Trepal’s extensive
knowledge of chemistry, as well as his possession of chemistry laboratory equipment, a number of toxic chemicals, and a homemade journal on poisons and poison detection in human organs. Finally, multiple experts uniformly testified that (1) the victims were poisoned by thallium, (2) thallium was found in both the empty and unopened Coca-Cola bottles in the victims’ home, and (3) thallium was found in a brown bottle in Trepal’s garage. Thallium is a heavy metallic element that is both rare and toxic to humans. When dissolved, it is odorless and tasteless. A lethal dose of thallium is approximately 14 milligrams per kilogram of body weight, which for an average person is around 1 gram of thallium.
The appeal involves fascinating Giglio claims regarding the FBI chemist, but in the end, the court finds them harmless. Harmless error regarding a lying chemist in a death penalty case seems like a hard (thallium?) pill to swallow.