Michael J. Parrish of Effort has been found guilty on two counts of first-degree murder in the shooting deaths of his girlfriend and their toddler son nearly three years ago.
The jury in the Monroe County case announced the guilty verdict just after 5 p.m. on Friday, only an hour and a half after closing arguments were heard.
Parrish could now face the death penalty for the double murders.
Parrish's attorney, Wes Niemoczynski, who told the jury that Parrish had killed the pair, claimed that the killings were not intentional; adding that Parrish's state of mind was not good the evening of the murders.
Assistant District Attorney Michael Mancuso argued that Parrish "is nothing but a controlling, abusive, hateful thug. He knew this ammunition was in the gun when he fired into his own son's face."
The jury must now report to the Monroe County Courthouse on Monday morning for the second part of the case.
The case against Parrish began on July 6, 2009, when Parrish, then 23, shot to death Victoria M. Adams, 21, and 2-year-old Sidney Michael Parrish in their apartment.
According to an affidavit of probable cause filed by State Police at Fern Ridge, at around 11 p.m., Adams had been brought to the apartment she and Parrish shared by three men, Keith Adams, James M. Ahern and Chris Ramos.
Parrish, armed, went outside and confronted the men, then ran back into the apartment.
Moments later, a neighbor heard gunshots and called police. Officers found shotgun shells and an empty pistol cartridge in the apartment.
Parrish was arrested on the evening of July 7 in New Hampshire, along with a friend, Conrad Jankow ski, 23, of Newfoundland, Wayne County.
State Police at Fern Ridge charged Parrish, who was a guard at the Monroe County Correctional Facility at the time, with homicide; and Jankowski with hindering apprehension.
On April 21, 2010, Parrish tried to plead guilty to the killings, but Monroe County President Judge Ronald Vican rejected the plea, calling Parrish's statements "a defense."
At that hearing, Parrish told the court that he felt rage when Adams came home that night, suspecting that she was cheating on him.