John Wayne Gacy I belive was last murderer exeecuted in the state of Illinois back 1994.
"Gacy committed all of his known murders inside his
ranch-style house. Typically, he would lure a victim to his home and dupe them into donning handcuffs on the pretext of demonstrating a magic trick. He would then rape and torture his captive before killing his victim by either
asphyxiation or
strangulation with a
garrote.
Twenty-six victims were buried in the
crawl space of his home, and three were buried elsewhere on his property; four were discarded in the
Des Plaines River.Gacy had previously been convicted in 1968 of the sodomy of a teenage boy in
Waterloo, Iowa, and was sentenced to ten years' imprisonment, but served eighteen months
He murdered his first victim in 1972, had murdered twice more by the end of 1975, and murdered at least thirty victims after his divorce from his second wife in 1976.
The investigation into the disappearance of
Des Plaines teenager Robert Piest led to Gacy's arrest on December 21, 1978.His conviction for thirty-three murders (by one individual) then covered the most homicides in United States legal history. Gacy was sentenced to death on March 13, 1980. He was executed by
lethal injection at
Stateville Correctional Center on May 10, 1994."
https://en.wikipedia.org/wiki/John_Wayne_Gacy