Tammy Zywicki case remains unsolved after 32 years, but DNA may revive investigation

Thirty-two years have passed since the disappearance and death of Tammy Jo Zywicki, an Iowa college student last seen after her car broke down on Interstate 80 near La Salle, and her case remains unsolved.

But Tammy’s friends, family and community have never stopped advocating on her behalf with the hopes of discovering renewed direction in her case, and her brother said authorities have been able to revive the case based on technological developments.

Todd Zywicki, Tammy’s oldest brother, said the Illinois State Police and the FBI have not let the case die and have continued to pursue it off and on throughout the years.

He said because of DNA technology advancements, police were able to recover some amount of DNA that they thought was previously unusable.

“I have heard that they were able to use that and get a usable sample,” he said. “And they are pursuing leads based on that. So, that is encouraging.”

The Illinois State Police responded to a request for comment on the case and DNA evidence, saying that the investigation still is open and ongoing, and no further information is available at this time.

Tammy, who grew up in Greenville, South Carolina, was killed Aug. 23, 1992, after dropping off her brother in Evanston and heading to Grinnell, Iowa, for college.

Nine days later, her body was found along Interstate 44 in rural Lawrence County, Missouri, between Springfield and Joplin. She had been stabbed to death.

Some of her personal belongings were never recovered, according to the FBI website, including a Cannon 35 mm camera and a Lorus-brand wristwatch. The watch had a green umbrella on its face and a green band that played the tune “Raindrops Keep Falling On My Head.”

Police said a tractor-trailer and its driver were spotted near Tammy’s car between 3:10 and 4 p.m. Aug. 23. The driver of the tractor-trailer was described as a white man with dark and bushy hair who was between 35 and 40 years older and more than 6 feet tall.

However, recent investigations, such as the Paper Ghosts podcast, have said that Tammy may have been abducted by a person of authority – someone she may have trusted and willingly got into the car with if they stopped to help.

In 2015, it was reported that the Philadelphia-based Vidocq Society, a pro bono service that provides assistance to the law enforcement community in solving cold case homicides, was delving into the case.

Shaw Local News Network sent a Freedom of Information Act request to state police in June, requesting the information they shared with the society.

State police responded with the following: “ISP is still actively investigating pending lab results in this case from the FBI, ISP and private labs. Additional investigative tasks may be conducted as a result of the pending lab results. Releasing the information at this time could compromise the investigation. ISP continues to analyze evidence and prepare reports.”

Years passed without any new leads until May 2020, when authorities in Iowa apprehended a long-haul trucker who had been implicated in the murder of three women in the 1990s and might be responsible for other homicides.

According to news reports at the time, a day later, Illinois State Police released the following statement: “At this time, [he] does not appear to have been involved with the murder of Tammy Zywicki, who was abducted and murdered by an unknown assailant after experiencing vehicle troubles alongside I-80 near La Salle, Illinois, in August 1992.”

“Somebody somewhere knows something,” Tammy Zywicki’s childhood friend Maryanne Fox said. “So, it’s just a matter of getting to those people and pulling on their strings.”

Fox said focus has shifted in the past year, noting that by continuing to keep Tammy’s name out, it not only invites people to come forward with new information but also spreads awareness to kids in high school who may be headed off to college.

“I think it’s about awareness,” she said. “Young college students, high school students: anywhere there are monsters that are out there and you need to be aware of your surroundings.

“It’s much better in today’s society because we have all of these electronic devices and cameras and ways of getting help that were not available back then, but to let people know Tammy would have led a successful life, loved by almost everybody that knew her, she had goals.”

Dean Zywicki, another older brother of Tammy, said he wants his sister to be remembered for the connections she was able to form with people of differing backgrounds.

“She was just really kind to people,” he said. “She had a different connection with all different people through different interests, whether it was soccer or photography or just trying to help.”

Anyone with information about the Zywicki investigation is asked to call the Illinois State Police’s Division of Criminal Investigations Zone 3 at 815-726-6377 or the FBI Chicago Field Division at 312-421-6700. Callers can remain anonymous.