Erie County District Attorney Michael J. Keane announces that Thomas F. Sibick, 40, of Williamsville, pleaded guilty this morning before State Supreme Court Justice Deborah A. Haendiges to one count of Criminal Possession of a Weapon in the Third Degree (Class D felony) and one count of Criminal Mischief in the Fourth Degree (Class A misdemeanor). Sibick entered a guilty plea to the highest count in full satisfaction of the indictment.
On Monday, June 8, 2026, the defendant and the victim were involved in an argument at a residence in the Village of Williamsville. While inside of the garage, the victim attempted to leave in a vehicle. The defendant pushed the car door open and grabbed the victim’s purse and phone charging cable, which damaged the cord. The defendant intentionally caused damage to the victim’s cell phone screen protector by throwing the phone onto the ground. After the victim left the home, she reported the incident to police.
At the defendant’s arraignment in Amherst Town Court, a temporary order of protection was issued on behalf of the victim, which required all firearms to be turned over to police. During the investigation, police seized several firearms and extended magazines from inside of the home. Police also separately recovered an upper and lower receiver that together created an operable semi-automatic rifle with assault weapon characteristics.
Sibick faces a maximum sentence of 7 years in prison when he is sentenced on Tuesday, November 17, 2026, at 9:30 a.m. He was released under supervision of the Probation Department. A temporary order of protection, issued on behalf of the victim, remains in effect.
DA Keane commends the Amherst Police Department for their work in this investigation.
The case was prosecuted by Assistant District Attorney Krista R. DeAntonis of the Domestic Violence Bureau.