BARRINGTON, IL – A suburban Chicago man is facing charges of first-degree murder following the shooting death of Dr. Olga Duchon, a prominent local endocrinologist, over the weekend.

William Zientek, 46, appeared in court on Wednesday, accused of the murder of his former girlfriend, Duchon, 42, who had recently shared her expertise on weight-loss medication with the Ukrainian Medical Association. Prosecutors allege the incident occurred in the presence of the couple’s three-year-old daughter.

The investigation utilized footage from Duchon’s Tesla to piece together the events leading to her death. Authorities claim Zientek had lured Duchon to his Barrington home on the pretext of having an important discussion. However, once inside, he reportedly assaulted her with a baseball bat, fatally damaging her skull, before shooting her in the chest.

Zientek allegedly contacted law enforcement, confessing to the shooting. His legal defense argues the act was in self-defense, suggesting that Duchon was armed at the time. However, prosecutors noted the firearm used was one Zientek had reported stolen over three years ago.

In courtroom proceedings, it was revealed that Duchon, who practiced internal medicine, endocrinology, and obesity medicine in Mundelein, was actively seeking court orders to prevent Zientek from accessing firearms, reflecting her fears for her safety.

Legal documents reveal Duchon had secured multiple protective orders against Zientek, citing concerns for her safety and that of their daughter, as well as her family. One such order was filed in November 2021 following an incident involving firearms left accessible around their home, particularly near where their daughter played.

Statements made by Duchon in her petition highlighted a history of threats, with Zientek allegedly warning of fatal consequences if she were to leave him or be unfaithful. By December 2021, she obtained an order mandating no contact with her ex-partner and enforced a safety perimeter of 200 feet.

Despite these precautions, court records from June 2022 show that a parenting agreement had been established, prioritizing the involvement of both parents in the upbringing of their young daughter. The agreement emphasized cooperation for the child’s best interests.

In light of the murder charges, the judge ruled that Zientek remain in custody without bail until his trial. Additionally, he is prohibited from contacting Duchon’s family, including his daughter. The case is set to continue, with further proceedings scheduled for next month.