The supposed aim of the demonstration was to reveal a method for escaping handcuffs without needing a key.

Once his victims were restrained, however, he subjected them to horrific torture, sexual assault, and eventually strangled them.

In spite of numerous survivors stepping forward to report Gacy’s crimes, law enforcement repeatedly dismissed him as a murder suspect.

Toward the end of 1977, he abducted a 19-year-old student at gunpoint, subjected him to rape and torture, and nearly drowned him multiple times in the bathtub.

In a rare move, he decided to let this particular victim go.

When authorities questioned him, Gacy managed to persuade them that he was involved in a consensual relationship with the victim, resulting in no charges being pressed.

Three months later, he abducted, raped and tortured another victim, 26-year-old Jeffrey Rignall.

Presuming he was dead, Gacy dumped Rignall’s body in parkland.

But Rignall came to, staggered to his girlfriend’s house and reported the assault to police.

But detectives did not investigate Gacy and did not actively pursue the case.

Determined to find his attacker, Rignall and three friends staked out an expressway exit for Gacy’s car, an Oldsmobile.

They eventually spotted him and followed him to his address. They then reported him to police.

Gacy was finally arrested and charged with Rignall’s assault and battery.

Despite this, Gacy was released on bail and went on to murder several other young men.

In December 1978, detectives linked Gacy to the disappearance of a 15-year-old.

In a police interview, he remarked to officers, “You know, clowns can get away with murder”.

When at his home, one officer noticed a foul smell coming from his heating vent.

Officers got a search warrant to start digging in Gacy’s crawl space for the missing 15-year-old.

Instead, they found the remains of 29 other young men.

During the trial, Gacy’s lawyers argued that all of his victims had died of accidental erotic asphyxia.

But the jury was not convinced, returning after less than two hours of deliberation.

He was found guilty of all 33 murder charges, the most of any American at that point in history.

He was sentenced to death.

His last words were: “Kiss my ass.”

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