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IOWA COLD CASES founder Jody Ewing compiled the following case summary using excerpts from sources listed at the bottom of this page. Though Tammy’s case is officially under Illinois State Police jurisdiction and the FBI’s Chicago Division, she has a page here due to her status as a Grinnell College (Iowa) student at the time of her death and because many wrote to say they felt she should be included here. We agree, and urge anyone with any knowledge about her unsolved murder to contact Special Agent Jorge Fonseca, Illinois State Police, at (815) 726-6377 Ext 286, or your nearest FBI office.
The FBI is offering a reward of up to $50,000 for information leading to the identification of the individual or individuals responsible for this crime.
On Sunday, Aug. 23, 1992, Tammy J. Zywicki, a 21-year-old Grinnell College student, departed Evanston, Illinois, to return to school in Grinnell, Iowa, where she planned to arrive that evening. Later that day, an Illinois State Trooper found Zywicki’s car — a 1985 Pontiac T1000 with New Jersey license plates — and ticketed it as an abandoned vehicle.
On Monday, Aug. 24, 1992, Illinois State Police towed the vehicle. That same evening, Zywicki’s mother contacted the Illinois State Police and told them her daughter had not arrived at college.
On Tuesday, Sept. 1, 1992, her body was found along Interstate Highway 44 (I-44) in rural Lawrence County, Missouri, located between Springfield and Joplin.
The petite blonde female had been wrapped in a red blanket bound with duct tape, been sexually assaulted, and stabbed eight times — once in the arm and seven times in a circle around her heart.
She’d reportedly last been seen with her car at mile marker 83 in central Illinois sometime between 3:10 and 4 p.m. on Aug. 23, 1992. Witnesses reported seeing a tractor-trailer near Zywicki’s vehicle during this time period.
Zywicki’s missing personal property included a Cannon 35mm camera and a musical wrist watch with an umbrella on its face.
Her murder attracted national attention, and Illinois State Police launched a multi-state 14-investigator task force that called in local forces and the FBI.
In January 1993, an unnamed eyewitness placed a call to the task force, stating she’d seen Zywicki pulled to the side of the road and that a man was with [Zywicki], watching as the young girl struggled to fix her car.
The witness described the man — allegedly the tractor-trailer’s driver — as a white male between 35 and 40 years of age, over six feet tall, and having dark, bushy hair.
The official FBI report confirmed Zywicki had last been seen in the presence of a man whose appearance resembled the eyewitness’ description.
The eyewitness reported yet another coincidence; she worked at a medical facility, and said the wife of the man who fit the truck driver’s description had come in for a routine blood test, and while there, told the eyewitness about a musical watch her husband had just given her. The timepiece matched the description of the one Zywicki had in her possession when she went missing, and investigators had never recovered the watch.
The eyewitness believed a strong connection existed between the events, and three days after the woman left the facility, the eyewitness contacted Martin McCarthy, a member of the investigative team who’d joined the federal task force in November 1992.
Officials identified the trucker as Lonnie Bierbodt and brought him in for questioning. Bierbodt provided both blood and hair samples for testing before being released.
A few weeks later in February 1993, the task force disbanded — citing lack of progress — and Tammy Zywicki’s homicide case eventually went cold.
The FBI marked the case’s 10-year anniversary with a renewed public plea for any information, and announced a $50,000 reward — which joined a standing $100,000 reward from an anonymous private source in Zywicki’s New Jersey hometown — for any information leading to an arrest in the case. FBI officials also confirmed for the first time that they’d collected DNA from Zywicki’s body 10 years earlier and had the evidence on file.
Along with the FBI’s newly released information, former task force member McCarthy came forward with allegations that Lonnie Bierbodt should have been arrested but was never formally held as a suspect. McCarthy also presented several previously unreleased facts, which he believed pointed to Bierbodt as a suspect. Those facts included:
Bierbodt also had a criminal record. He’d committed two armed robberies in the ’80s and officials considered him a “violent felon.” At one time he’d been serving three concurrent 20-year sentences before being released and paroled in 1990.
Lonnie Bierbodt died in June 2002 at age 41. Martin McCarthy retired as a master sergeant for the Illinois State Police the following month.
In July 2007, FBI agents contacted investigators in Tennessee about questioning 56-year-old trucker Bruce Mendenhall in Zywicki’s slaying. Mendenhall, of Albion in southern Illinois, was arrested Thursday, July 12, 2007, and charged with killing 25-year-old Sara Hulbert at an interstate truck stop in Nashville, Tenn.
Mendenhall eventually confessed to killing six women at truck stops in Tennessee, Indiana, Alabama, and Georgia. He didn’t confess to Zywicki’s death, but Ross Rice, an FBI spokesman in Chicago, said it was the agency’s duty to question Mendenhall.
“We have an over-the-road trucker who is accused of murdering at least one woman who was abducted in a roadside situation, which is exactly what happened in the Zywicki case,” Rice told the press after Mendenhall’s arrest. “I think it would be a dereliction of our duties if we didn’t look into it.”
Although hopes were temporarily raised for closure in Zywicki’s homicide, investigators never charged Mendenhall in the Grinnell student’s death.
The 20th anniversary of Tammy Zywicki’s unsolved murder did not go unnoticed.
In “Remembering what Tammy Zywicki would have liked,” Chicago Tribune writer Mary Schmich wrote an especially poignant piece about the journey JoAnn and Hank Zywicki made from their Florida retirement home to the small Pennsylvania town where they — and Tammy — were born.
FBI officials in Chicago said they hoped the $50,000 reward would help resolve Zywicki’s case.
On the eve of the 20th anniversary date, the head of Illinois State Police insisted investigators hadn’t forgotten the case. As the Des Moines Register reported on Aug. 22, 2012:
“This investigation remains a top priority, both for me personally as well as the men and women” of the agency, State Police Director Hiram Grau said, noting that authorities “are committed to bringing justice and peace to the Zywicki family.”
A Greenville News article published Jan. 22, 2015 said Illinois State Police turned to the nationally known organization, the Vidocq Society, for help in solving Zywicki’s murder.
The Greenville News described the Vidocq Society as follows:
The Vidocq Society began with a 1990 luncheon involving three men from various specialties in criminal investigation — a former special agent for the U.S. Customs Service, a forensic sculptor and a prison psychologist. Their intent was simply to eat well and discuss crimes and mysteries.
Before long, they had formed a more formal group and narrowed its interest to cold cases. Now, the society has a membership of about 150 people from all areas of criminal investigation.
The society’s name comes from Eugene Francois Vidocq, who is considered the founder of modern criminal investigation. A thief who spent some years in prison, Vidocq became an informant to the police and ultimately founded a private detective agency in the early 1800s. He is credited with developing modern record keeping, the science of ballistics and making plaster of Paris casts of shoes.
Retired Illinois State Police investigator McCarthy still believes trucker Lonnie Bierbrodt is responsible for Zywicki’s murder, and would like to see a grand jury empaneled to hear the evidence.
McCarthy also wants Gov. Bruce Rauner to assign a special prosecutor to investigate the student’s death, NBC Channel 5 News reported Tuesday, Jan. 20, 2015.
The NBC News story said McCarthy and Zywicki’s parents believe error after error was made in the days following the coed’s disappearance that cost them answers and likely precious physical evidence. The retired officer said he’s pressing Rauner to assign a special prosecutor to look into the case.
“I feel so sorry for [JoAnn and Hank Zywicki]. I don’t think they’ve been well-served,” McCarthy told the Chicago NBC network. “We’ve come to the point where we have a lot of evidence. We have a suspect. We need a grand jury. We need the power of the grand jury,” he explained.
According to Master Sgt. Padilla, State Police investigators presented evidence in Zywicki’s death to Vidocq Society members in Philadelphia in November 2014 and have been following up on their suggestions.
Padilla declined to discuss the new avenues of investigation, and said investigators have not shared with the family all that they have done for fear of compromising the investigation, the Greenville News reported.
Padilla said there has never been a main suspect in the case, and that several people — some still living — were being investigated.
Henry “Hank” Zywicki, 75, died Tuesday, May 26, 2015, in Ocala, Florida, without ever seeing justice served in his daughter’s unsolved murder.
Tammy Jo Zywicki was born March 13, 1971, in Pleasant Hill, Pa.
Mass was held at the Catholic church in West Newton, Pa., on Tuesday, Sept. 8, 1992, with burial in the West Newton Memorial Cemetery in Westmoreland County.
Tammy was survived by many loving friends and relatives, including her parents, Jo Ann and Hank Zywicki, and three brothers, Todd, Dean, and Daren.
Will new reward crack Iowa cold case? Video by KCCI Des Moines, August 23, 2012
If you have any information about Tammy Zywicki’s unsolved murder please contact your local FBI office, the nearest American Embassy or Consulate, or Special Agent Jorge Fonseca, Illinois State Police at (815) 726-6377 ext 286.