A Lisle man pleaded guilty Monday to killing a Darien man by providing him the fentanyl-laced heroin on which the man overdosed.
Adam Roser, 38, of the 5100 block of Lincoln Avenue, pleaded guilty to one count of drug-induced homicide.
Roser will be sentenced June 21. He could be sentenced to up to 30 years in prison.
Andrew Sasnau, 19, died Aug. 2, 2019, in the living room of his home. Police found a string of text messages between Sasnau and Roser on Sasnau’s cellphone to set up the drug purchase.
After the sale, Roser texted Sasnau asking about the quality of the drugs. Sasnau texted back that they were good, and Roser replied, “Thanks. I mixed them up myself,” a prosecutor said at the initial bond hearing in 2019.
Roser previously had pleaded guilty to a 2013 charge of aggravated battery. He had been shooting heroin at a woman’s home and her boyfriend asked Roser to leave. After leaving, Roser returned, kicked in the front door and beat the man with a police-style telescoping baton.
Roser also pleaded guilty to a 2013 charge of possession of a controlled substance, Xanax pills, and was sentenced to 18 months in prison. In a 2010 case, he pleaded guilty to possession of ketamine.