Prosecutor: Summerwill was intoxicated the night he killed his mother

Campton Hills man pleads guilty to involuntary manslaughter in plea deal

ST. CHARLES TOWNSHIP – The night Thomas Summerwill beat his mother to death with a baseball bat, he was intoxicated, his blood alcohol measured at 0.27.

Appearing in court Wednesday before Kane County Associate Judge Salvatore LoPiccolo, prosecutor Greg Sams read a description by Campton Hills police responding to a 911 call March 24, 2019, where they found Summerwill holding a towel to his mother’s bleeding head and crying, “I didn’t know it was my mom!”

Summerwill had said that he “woke up in a daze” and thought his mother was an intruder in his bedroom, Sams said.

Sams amended the charges against Summerwill to include felony involuntary manslaughter of a household member, in “exchange for a guilty plea.”

LoPiccolo accepted the sentence for Summerwill of 48 months of probation and 200 hours of community service.

Sams also described numerous injuries to Mary Bridget Summerwill’s head and body, including an injury so deep, her brain matter was present.

Mary Summerwill, 53, was pronounced dead of her injuries at Northwestern Medicine Delnor Hospital in Geneva, Sams said.

Summerwill was also taken to Delnor, where his blood was drawn, showing not only the level of alcohol but that he also had marijuana in his system, Sams said.

Summerwill, 23, was originally charged and indicted on two counts of second-degree murder in the death of his mother.

The indictments had stated that if Mary Summerwill had been an intruder, his actions would be justified, but that Thomas Summerwill’s belief that she was an intruder was unreasonable.

The terms of his probation require that Summerwill cannot use alcohol, must wear an alcohol monitoring device for a year, then be subjected to random testing by court services, continue in the Lighthouse addiction recovery program, continue in grief counseling, follow recommendations of his psychological assessment and not commit any other criminal acts.