A Marengo man has been sentenced to 28 years in prison after he pleaded guilty to killing his ex-girlfriend from McHenry County after her body was found “partially mummified” in a storage unit.
Michelle Arnold-Boesigner, 33, of Harvard, was reported missing to the Holiday Hills Police Department on January 3, 2021.
The Holiday Hills Police Department later turned the investigation over to the McHenry County Sheriff’s Office the same month.
Through the course of the investigation, probable cause was established to obtain a search warrant at the U-Haul Storage of Roscoe, 12522 North 2nd Street in Roscoe, the McHenry County Sheriff’s Office said.
The McHenry County Sheriff’s Office, Winnebago County Sheriff’s Office, Wisconsin Department of Criminal Investigations and Roscoe Police Department executed the warrant search on March 2, 2021.
Officers found a deceased body inside the storage unit at the facility, according to the McHenry County Sheriff’s Office.
The Winnebago County Coroner’s Office identified the body as Arnold-Boesigner.
Winnebago County State’s Attorney J. Hanley said that Arnold-Boesigner’s body was found in the storage unit inside a black Jeep Renegade registered to Jonathan J. Van Duyn, 35, of Marengo.
Arnold-Boesigner’s body was “in a state of purification and was partially mummified.”
Hanley said phone records placed Van Duyn with Arnold-Boesigner at the storage facility in mid-November 2020.
Hanley also said that the woman’s debit card was used to purchase “odor-eliminating products” along with heavy-duty garbage bags and Gorilla tape, which were found in Van Duyn’s Jeep.
Van Duyn used Arnold-Boesigner’s debit card multiple times for several weeks after he is alleged to have killed her, Hanley said.
Van Duyn was charged in December 2019 in McHenry County with aggravated domestic battery by strangulation, two counts of domestic battery and one count of criminal damage to property.
Van Duyn, who was Arnold-Boesigner’s boyfriend, was accused of stealing the woman’s pain medication and strangling her in July 2019, according to an order of protection petition that she filed shortly after that incident.
Arnold-Boesigner claimed that Van Duyn bit her lips to get her to stop yelling and continued to strangle her until she nearly blacked out, the order of protection petition said.
“I am afraid of what Jonathan may be capable of, especially now that the police and courts have become involved. I am afraid for my safety,” Arnold-Boesigner said at the end of her petition.
Van Duyn was charged in the woman’s murder after a grand jury indicted him on two counts of first-degree murder and one count of concealing a homicidal death, according to court records.
Van Duyn was arrested in Indiana in December 2021. He was transported to the McHenry County Jail on the domestic battery charges and later extradited to Wisconsin for an unrelated criminal case.
The Wisconsin case involved Van Duyn being charged with kidnapping his daughter. He has been sentenced to over seven years in prison for that case.
Court records show Van Duyn on Friday entered into a negotiated plea deal in Winnebago County for Arnold-Boesigner’s murder.
He pleaded guilty to one count of first-degree murder in exchange for his other two charges being dismissed.
Winnebago County Judge Jennifer Clifford approved the plea and sentenced him to 28 years in the Illinois Department of Corrections.
Van Duyn remains held in Winnebago County pending transport back to Wisconsin to first serve his kidnapping sentence.