Judge rules mental illness played role in Troy man’s knife attack on his mother

A Madison County judge has found a man accused of trying to murder his mother at her Troy home not guilty by reason of insanity, and ordered that he be held indefinitely in a secure setting.

Gabriel H. Kammerer, who was 20-years-old at the time of the incident, was charged in December 2023 with attempted first degree murder and home invasion, both Class X felonies; aggravated unlawful restraint and aggravated battery, both Class 3 felonies; and aggravated domestic battery, a Class 2 felony in Madison County Circuit Court.

According to the indictment, Kammerer entered the home of Theda Kammerer, his mother, without permission on Dec. 23, 2023, held her at knifepoint and stabbed her in the abdomen and neck. The indictment says he also cut her hands, arms and legs.

On June 22, Madison County Circuit Judge Amy Maher found Kammerer not guilty of attempted first-degree murder by reason of insanity. The order says prosecutors agreed to dismiss the other charges against Kammerer and that Kammerer is to be confined in a secure setting indefinitely, but no longer than June 1, 2049.

Kammerer appeared in court via Zoom from Elgin Mental Health Center.

The order says evidence shows Kammerer is guilty beyond a reasonable doubt of attempted murder, but that there is clear and convincing evidence that because of mental illness, he “lacked the capacity to understand the criminality of his conduct” at the time of the alleged offenses.

Court records show the decision came after multiple psychological evaluations. The court first found Kammerer unfit to stand trial in November 2024, and he has remained in the custody of the Illinois Department of Human Services.

In a Dec. 27, 2023, news release about the incident, Troy police said officers responded to a home in the 500 block of Lanahan Drive after receiving an open-line 911 call in which a dispatcher heard a woman screaming for help.

When police arrived, Kammerer was crouched over his mother and trying to stab her in the neck, according to a prosecutor’s petition to detain Kammerer pending trial.

Theda Kammerer was taken by ambulance for medical treatment, the Troy Police news release says.

Kammerer’s mother told police she had told her son he could no longer stay at the residence because the homeowner earlier that year sought an order of protection after he threatened to kill the homeowner with a knife, according to the prosecutor’s petition.

BND reporter Lexi Cortes contributed to this report.