A judge found a Plainfield Township man guilty of the first-degree murder of a girlfriend who was brutally beaten to death in 2018 in Romeoville.

Will County Judge Vincent Cornelius spent about 20 minutes on Tuesday explaining why he found George Hooper, 42, guilty of intentionally beating Jennifer Underhill, 42, of Rochelle, in a brutal manner, on July 23, 2018.

Cornelius also found Hooper’s crime was committed with “exceptionally brutal or heinous behavior indicative of wanton cruelty.”

That finding could lead to Hooper facing natural life in prison.

Hooper’s sentencing is scheduled for July 30.

Cornelius’ courtroom was packed on Tuesday with family and friends of Underhill. Many of them wore hoodies in memory of Underhill.

Tonia Underhill, the sister of Jennifer Underhill, was one of them. She was in tears after Cornelius delivered his verdict. She hugged assistant state’s attorneys Amanda Tasker, Jacob Kreutzer and Nick Plattos outside the courtroom.

Tonia Underhill said she was “very satisfied” with Cornelius’ verdict.

“It’s been a long time in the making,” she said.

The case had been pending trial for almost eight years.

After the verdict, George Hooper was calm as Will County sheriff’s deputies put him back in handcuffs and led him out of the courtroom.

The events leading to Jennifer Underhill’s death began when Hooper suspected she was having an affair with his brother, Geremy Hooper, 40, of Villa Park, according to prosecutors.

George Hooper joined his brother’s girlfriend, Amanda Weck, 41, of Villa Park, in trying to find Jennifer Underhill and Geremy Hooper, according to prosecutors.

Cornelius said the evidence showed George Hooper found Jennifer Underhill in a “compromising position” with Geremy Hooper.

Prosecutors said George Hooper found his girlfriend with his brother inside a semitrailer near a warehouse in Romeoville. Geremy Hooper told detectives in 2018 that his brother had smashed the window to the semitrailer and pulled a gun on him.

Weck told detectives she saw George Hooper striking Jennifer Underhill before she left the scene, and Geremy Hooper had also left the area after his brother had threatened to shoot him, according to prosecutors.

Cornelius said George Hooper admitted to police that he punched Jennifer Underhill twice and she fell to the ground.

But Cornelius found Jennifer Underhill’s autopsy was “not consistent” with George Hooper “merely” punching her twice and her falling on the ground.

Cornelius noted the extensive bruises and abrasions all over Jennifer Underhill’s body. She suffered a broken jaw, broken ribs and pattern bruising suggesting she was struck by an object, according to Valerie Arangelovich, a forensic pathologist.

Cornelius said George Hooper showed “consciousness of guilt” by leaving Jennifer Underhill in a location that concealed her body. Prosecutors said her body was found by police in a tall brush area near a Romeoville warehouse with her ankles tied with her shirt.

Cornelius said George Hooper also showed “consciousness of guilt” when he fled to southern Illinois, where he was apprehended by police following a traffic stop.

Cornelius said George Hooper expressed remorse in his interviews with detectives but that, too, was also evidence of guilt.

Cornelius was not persuaded by defense arguments that George Hooper was guilty of the lesser offense of second-degree murder because he was provoked by the discovery of the affair.

He said the evidence showed George Hooper, before the confrontation, had removed the license plates to Jennifer Underhill’s vehicle, which was at the scene along with the semitrailer in Romeoville.

He said that suggested “pre-planning and calculation.”

Cornelius noted George Hooper had managed to “exercise restraint” when he had pulled a gun on his brother, after seeing him with Jennifer Underhill.