NORTHAMPTON — The defense for Steven Malloy, who is facing a charge of first-degree murder in the 2021 shooting death of Joseph Fillio, continued to question witnesses on day four of the trial Friday, with a focus on the existence of a cat described by a key witness in the case.

Fillio died on Dec. 1, 2021 from a gunshot wound to the head during a party at the apartment of Jessica Dupell, situated on the corner of Randolph Place and Pleasant Street in Northampton. Police arrested Malloy, who was at the party, later that night and charged him with murder as well as unlawful possession of a firearm. Malloy has pleaded not guilty to the charges and his defense attorney, Joseph Perullo, has implied that Fillio may have shot himself and had a past history of suicidal behavior.

Todd Wilchek, who also was at the apartment that evening, is the only witness who claims to have directly seen Malloy shoot Fillio in the kitchen of the apartment. During testimony Wednesday, Wilchek told prosecutor Matthew Thomas that he saw Malloy pull out a gun suddenly and asked, “Have you seen one of these before?” Wilchek said that Malloy walked very close to Fillio and put the gun to Fillio’s temple before he heard the “pop” of the gun go off and Fillio collapse to the ground.

During cross-examination by Perullo on Thursday, Wilchek said he also remembered playing with a kitten in the apartment when he visited that night. Another witness, Michael Knowlton, the first police officer to respond to the scene, had testified he did not see a cat when asked about it by Perullo.

On Friday, Perullo again posed that question to witness Clay Delano, who at the time was a patrol officer for the Northampton Police Department and had also responded to the scene the night of Fillio’s death. Perullo asked Delano if he had seen a cat in the apartment when canvassing it in searching for the gun allegedly used to kill Fillio, which has yet to be recovered. He also asked if Delano saw any signs that a cat may have lived in the apartment, such as cat food or a litterbox.

“I can’t say that one way or another. I don’t recall that,” Delano said. “I don’t necessarily know that a kitty litter box would stand out when there’s a homicide on the floor.”

Perullo then asked if it would matter to police if a witness claimed to see a cat in the apartment if there was in fact none present. This raised an objection from Thomas, which Judge James Manitsas sustained.

Friday also saw testimony from Amanda Osborne, a foresnic scientist at the Massachusetts State Police Crime Lab in Springfield. Osborne said she had Malloy tested for gunshot residue and tested blood on his sneakers that matched Fillio’s blood.

Perullo asked Osborne if it was possible for someone to have gunshot residue if someone who fired a gun made physical contact with them, which Osborne said was possible. He also asked if anyone else who was present at the apartment had their shoes tested for blood, which Osborne said they did not. Perullo said during his opening arguments that anyone present at the time of Fillio’s death would have had blood on their shoes.

On redirect, Thomas asked Osborne, who later visited the apartment for some screening tests for blood that was at the scene, if she was able to get in and out of the apartment without getting blood on her shoes.

“Oh, certainly,” Osborne responded. “There was a lot of area that did not have red-brown stains or saturated areas of red-brown.”

The trial is expected to continue Monday morning at Hampshire Superior Court.

Alexander MacDougall can be reached at amacdougall@gazettenet.com.