Man tried poisoning exes with cyanide in water, car air vent, WI prosecutors say
A detailed plan to poison a man’s ex-girlfriends has led to the arrest of the former boyfriend and a woman identified as the “brains of the operation,” Wisconsin prosecutors said.
Paul Van Duyne, 43, is accused of breaking into his ex-girlfriends’ cars and putting cyanide in their water bottles, Dane County Deputy District Attorney William Brown said during a bond hearing posted by WJFW.
He was charged with two counts of intentional homicide and one count of stalking in Dane County and three counts of attempted intentional homicide, aggravated battery, stalking and recklessly endangering safety in Rock County.
Van Duyne’s attorney did not immediately respond to McClatchy News’ request for comment on June 20.
Once in jail, Van Duyne made a call to Andrea Whitaker, 41, and asked her to remove a computer and boxes from his Madison home, Brown said during the June 18 hearing. Whitaker was arrested on June 16 when police reported catching her removing the items from the home, prosecutors said.
Prosecutors believe the boxes contained the poison used in the attempted killings of women Van Duyne had previously dated, Brown said.
Whitaker was charged with aiding a felon in Dane County on June 16 and three counts of attempted intentional homicide, aggravated battery, stalking and recklessly endangering safety in Rock County on June 19, according to jail records. Her attorney’s information was not available in court records.
Van Duyne broke into a woman’s car while she was at Costco and put cyanide in her water left in the vehicle, according to prosecutors. When the woman returned to her car, prosecutors said, people nearby said it had been broken into.
She took a drink of her water and spit it out because it tasted bad. A couple of weeks later, while at Costco again, the same thing happened, Brown said.
In Rock County, another woman had a similar experience, according to Brown. In addition to cyanide in her water, poisonous powder was also put in her air vents, prosecutors said. She was hospitalized due to exposure to the substance.
In her bond hearing, Whitaker’s attorney argued there was no evidence the woman knew removing the items from Van Duyne’s home was wrong.
However, Brown said Whitaker’s phone showed searches for cyanide, lethal doses of the poison and if cyanide powder goes bad.
Hazmat searches were conducted in Madison by the Wisconsin National Guard and the FBI, WKOW reported. Some agents were hospitalized due to possible exposure from the poison, according to Brown.
Whitaker is held in jail on a $750,000 bond in Dane County, a judge ordered.
Rock County is about a 50-mile drive southeast from Dane County.
This story was originally published June 20, 2025 at 11:58 AM with the headline "Man tried poisoning exes with cyanide in water, car air vent, WI prosecutors say."
