A 46-year-old man was charged with first-degree murder in the shooting death of a north suburban endocrinologist he shares a child with, Barrington police announced Tuesday.
William R. Zientek is accused of shooting and killing Olga Duchon, 42, Sunday in the 400 block of West Russell Street in what police described as a domestic dispute. Police officers found Duchon around 5:40 p.m. with an apparent gunshot wound. She was taken to Advocate Good Shepherd Hospital in Barrington where she was pronounced dead, police said.
The Lake County coroner’s office determined Duchon, of Vernon Hills, died from a single gunshot wound to her chest, police said. Zientek resides at the same Barrington address where the shooting occurred, police said.
Duchon, a well-known endocrinologist, filed an emergency order of protection in McHenry County against Zientek on Nov. 17, 2021, alleging that Zientek had guns in his home and that she feared for her life. The petition notes that the two shared a young child.
Duchon wrote that her mother called her at work to say she found a gun on the couch and did not feel safe alone in the house with Zientek, according to the petition. Duchon called the police and came home to learn that Zientek had multiple weapons, but had also reported some guns missing.
“I had to leave the house as (I) did not feel safe there and ‘missing gun’ is a lie and makes me scared for my life and my daughter’s life,” the petition said.
Duchon also said in the petition that in the past Zientek threatened to kill her if she left him or cheated on him.
“I am unable to sleep, my daughter (is) having difficulties adjusting to new environment and unable to sleep. I am and my parents (are) afraid to go on walks outside,” she wrote. “I am unable to concentrate and perform at work, missing days and now office staff now feels unsafe and adding security to multiple buildings.”
In December 2021, a McHenry County judge signed an order that said both parties should stay away from each other except when facilitating parenting time.
On Dec. 2, 2021, Zientek filed a petition asking for parenting time with their daughter, born in 2020, according to McHenry County court records. About six months later, Duchon and Zientek agreed to a shared parenting schedule and responsibilities.
Just hours before she was killed, Duchon was the featured speaker for a lecture on obesity management in Wheeling, according to Maria Hrycelak, president of the Ukrainian Medical Organization of North America Foundation. She called Duchon “a very bright, smart, well-trained young lady.” Duchon previously worked for the Northwestern University health system until 2023.
Zientek’s initial court appearance is scheduled for Wednesday.