The lead investigator of the John Wayne Gacy case spoke at NIU on Wednesday evening.

Students crowded in a Neptune Central smart classroom to hear Lt. Joseph Kozenczak speak about his experiences while investigating the serial killer John Wayne Gacy. Gacy was convicted of killing 33 young boys in the 1970’s and was sentenced to death. Gacy was known as the killer clown because he used to perform as “Pogo the Clown” at birthday parties.

The event was sponsored by the Exploring Majors House. Nathan Hilse, junior physical therapy major attended the event and said he was surprised by the information that Kozenczak shared.

“I was blown away by the fact that he was so willing to share the information given the sensitivity of the subject manner,” Hilse said.

Kozenczak spoke in detail about his interactions with Gacy, what he saw in Gacy’s house and how Gacy was arrested.

Kozenczak claimed the investigation started when 15 year old Robert Piest, who was Gacy’s final victim, went missing. Piest was dropped off to go to work at a local pharmacy in Des Plaines and was to be picked up later that evening. Piest’s mother entered the drug store while her son was speaking to Gacy and when she came back out of the store, her son, Robert, was gone.

Kozenczak and other investigators went to Gacy’s house to interrogate him about the missing young man. Kozenczak confiscated handcuffs, belt buckles and miscellaneous IDs during the search of Gacy’s home. Investigators also found the sealed crawl space that Gacy had hidden 27 bodies, but did not know about the bodies because there was no foul odor. The other six bodies had been disposed in the Des Plaines river.

Looking back at the events, Kozenczak was upset that he did not know a body was right in front of him.

“The saddest part of the whole case was when I was interviewing Gacy about the missing boy, Robert Piest was literally right above me already murdered,” Kozenczak said.

After the interrogation, Gacy had turned on his sump pump which flooded his crawl space on accident. The flood started to cause the human remains to have a foul scent, Kozenczak said.

Gacy tried to form a unique relationship with the detectives by buying them drinks at the bar, and eventually invited two detectives over for dinner. The two detectives took the invite to get more information and another chance to see the house. During dinner, the detective went into Gacy’s bathroom when the heat went on and the odor of the remains came through the vents.

Kozenczak explained the detectives contacted him immediately about the odor and claimed it smelled like a morgue under his house. As they were in the process of requesting a second search warrant, Gacy was caught and arrested for making a drug deal. While Gacy was in jail, the investigators found the bodies in the crawl space.

Gacy never made a written confession, but verbally admitted to killing the boys and bringing the final six bodies to the Des Plaines river at 3 a.m. Gacy was executed in May, 1994, in Illinois.

Mike Kozenczak, Hanover police officer and son of Joseph Kozenczak, remembers his father being more protective of him and his siblings during the investigation.

“I remember being told if someone calls the school, to not leave with them,” Kozenczak said. “I think they were worried that Gacy would try to attack our family.”