A man has been arrested by a law enforcement task force and charged with homicide for allegedly providing the drugs that led to a woman’s overdose death in Lake in the Hills.
The Illinois State Police North Central Narcotics Task Force and Lake in the Hills Police Department worked together to arrest a suspect on Thursday in connection with a drug-induced homicide that occurred last year, according to Lake in the Hills Police Department Communications Coordinator Blaine Krage.
Karl M. Petermann VI, 43, of Lake in the Hills, was charged with one count of drug-induced homicide, a Class X felony; one count of manufacturing or delivery of a controlled substance, a Class 2 felony; and possession of a controlled substance, a Class 4 felony.
The charges stem from an incident that the Lake in the Hills Police Department responded to around 5:03 p.m. on July 25, 2025, in the 1300 block of Cunat Court in Lake in the Hills.
Officers arrived and found a woman who was deceased at the scene, Krage said.
The McHenry County Coroner’s Office identified her as Heather Bartolai, 41, of Bristol, Wisconsin.
A task force investigation conducted over several months showed that Petermann “knowingly and with intent” provided cocaine to Bartolai prior to her death, Krage said.
The coroner’s office confirmed that Bartolai’s cause of death was from cocaine toxicity.
Prosecutors said Petermann provided crack cocaine to Bartolai at his apartment in Lake in the Hills.
Bartolai ingested the drugs and suffered the fatal overdose later that same day.
Court documents said Bartolai had heart issues, which Petermann knew, and she had an appointment scheduled for a pacemaker the very next day.
“The loss of life resulting from illegal drug distribution continues to devastate families and communities,” McHenry County State’s Attorney Randi Freese said.
“Our office remains committed to working alongside law enforcement to investigate every overdose death in McHenry County and to hold accountable those who provide the drugs that lead to these tragic and preventable fatalities. We extend our deepest condolences to the victim’s family and loved ones,” Freese said.
Petermann was processed at the Lake in the Hills Police Department after his arrest and transported to the McHenry County Jail.
The McHenry County State’s Attorney’s Office filed a petition to detain Petermann pending trial, arguing he poses a danger to the community.
Petermann appeared for an Initial Appearance Court hearing on Friday afternoon.
McHenry County Judge Joel Berg granted the petition after noting that Petermann has a prior conviction for dangerous drugs and was doing them in the “most ridiculous situation imaginable.”
Court documents indicated that the victim and others were partying because she was scheduled to get the pacemaker the next day.
“This Court cannot imagine a more ridiculous threat or any conditions or combination of conditions which could mitigate that threat. Electronic monitoring could not prevent him from giving drugs to anyone if he is willing to give them to someone who is going on to heart appointment the next day,” Berg said.
Petermann is scheduled to appear in court again on June 26 for a status of trial date.