Claim: John Wayne Gacy Jr. murdered three or more people.

John Wayne Gacy Jr. -LRB- March 17 , 1942 -- May 10 , 1994 -RRB- was an American serial killer and rapist . He sexually assaulted , tortured and murdered at least 33 teenage boys and young men between 1972 and 1978 in Cook County , Illinois -LRB- a part of metropolitan Chicago -RRB- .   All of Gacy 's known murders were committed inside his Norwood Park ranch house . His victims were typically lured to his address by force or deception , and all but one of his victims were murdered by either asphyxiation or strangulation with a makeshift tourniquet ; his first victim was stabbed to death . Gacy buried 26 of his victims in the crawl space of his home . Three other victims were buried elsewhere on his property , while the bodies of his last four known victims were discarded in the Des Plaines River .   Convicted of 33 murders , Gacy was sentenced to death on March 13 , 1980 for 12 of those killings . He spent 14 years on death row before he was finally executed by lethal injection at Stateville Correctional Center on May 10 , 1994 .   Gacy became known as the `` Killer Clown '' because of his charitable services at fundraising events , parades , and children 's parties where he would dress as `` Pogo the Clown '' , a character he devised himself .