A forensics expert hired to examine the gun that discharged while Alec Baldwin was rehearsing with it on the set of the film “Rust” in New Mexico, killing the movie’s cinematographer, has issued a new report that determined the actor must have pulled the trigger, a conclusion at odds with his account.
Since the fatal shooting of the cinematographer, Halyna Hutchins, in October 2021, Mr. Baldwin has said that he had pulled the hammer back and let it go just before the gun discharged, maintaining that he did not pull the trigger. The revolver was supposed to be loaded with dummy rounds, inert cartridges used to make it appear loaded on camera, but it turned out to be loaded with a round of live ammunition.
Prosecutors have been skeptical of his claim that he did not pull the trigger, and in January Mr. Baldwin was charged with involuntary manslaughter in connection with the case. A new set of prosecutors dismissed the charges against him in April, saying new evidence suggested that the gun Mr. Baldwin had been rehearsing with that day might have been modified, potentially making an unintentional discharge easier.
The prosecutors said at the time that they would consider refiling charges against the actor after a new examination of the gun.
The report from the forensics expert, Lucien C. Haag, did not directly address whether the gun had been modified. But it concluded that the old-fashioned Pietta revolver would have needed about two pounds of pressure on the trigger to discharge a round.
“Although Alec Baldwin repeatedly denies pulling the trigger, given the tests, findings and observations reported here, the trigger had to be pulled or depressed sufficiently to release the fully cocked or retracted hammer of the evidence revolver,” Mr. Haag wrote in the report, which was released through a public records request. He also included photos of Mr. Baldwin handling a revolver on set earlier in filming, highlighting the actor’s finger on or near the trigger as he was cocking the gun.
The finding aligns with an earlier examination by the F.B.I.
Kari T. Morrissey, one of the prosecutors now handling the case, said on Wednesday that a final decision had not been made on whether to revive the charges against Mr. Baldwin and that “minimal additional testing of the gun may be warranted.”
In his report, Mr. Haag noted that parts of the revolver were broken at the time he received it and that, in order to test it, he had to replace those parts with new ones. Lawyers for Mr. Baldwin have previously raised questions about how such a damaged gun can be properly examined.
A lawyer for Mr. Baldwin, Luke Nikas, did not immediately respond to requests for comment. Mr. Baldwin pleaded not guilty to the initial charges, and he and his lawyers have maintained that he was not responsible for the death of Ms. Hutchins, saying that he was told that day that the gun was safe to handle.
Mr. Baldwin has said that he was told that the gun did not have live rounds in it, and that he was only following directions when he pointed it toward the cinematographer. “Someone is responsible for what happened, and I can’t say who that is, but I know it’s not me,” he said in a 2021 television interview. He later filed a lawsuit against several people associated with the film — including its armorer and first assistant director — accusing them of negligence for giving him a loaded gun on the set.
Hannah Gutierrez-Reed, the armorer who was responsible for guns and ammunition on the set and who loaded the revolver that day, was being charged with involuntary manslaughter and evidence tampering in the case. She pleaded not guilty and is scheduled to stand trial in December.