The trial of the armorer on the film “Rust” who was convicted of involuntary manslaughter this week for putting live ammunition into a gun that went off on the set and killed the cinematographer, offered a preview of the criminal case prosecutors are building against Alec Baldwin, who was handling the gun when it fired. A grand jury indicted Mr. Baldwin in January on a charge of involuntary manslaughter, which carries up to 18 months in prison. He pleaded not guilty; his trial is set for July. Baldwin was practicing drawing an old-fashioned revolver when the gun fired on Oct. 21, 2021, killing the film's cinematographer, Halyna Hutchins, and wounding its director. He has denied responsibility from the beginning, telling investigators that he had been told the gun did not contain live ammunition, and noting that live ammunition was supposed to be banned on the set. He also denied pulling the trigger, saying that the gun went off after he pulled its hammer back and released it; a forensic analysis commissioned by prosecutors found that he must have pulled the trigger for it to go off. Prosecutors have argued that Mr. Baldwin failed to observe firearms safety measures. "Alec Baldwin's conduct and his lack of gun safety inside that church on that day is something that he's going to have to answer for," Kari T. Morrissey, the lead prosecutor in the case, said during the closing arguments in the trial of the film's armorer, Hannah Gutierrez-Reed. "That'll be with another jury on another day." Some of the evidence and testimony presented at the trial of Ms. Gutierrez-Reed could help Mr. Baldwin's case; other things that emerged in court could undermine it. Hutchins, who was 42 when she died, grew up on a remote Soviet military base and worked on documentary films in Eastern Europe before studying film in Los Angeles and embarking on a promising movie-making career. She described herself in social media posts as a "restless dreamer" and "adrenaline junkie." Friends and family said she was well-liked and had a magnetizing personality. Hutchins' parents and sister responded to Gutierrez-Reed's conviction by saying they've always wanted accountability for her death. "We look forward to the justice system continuing to make sure that everyone else who is responsible for Halyna's death is required to face the legal consequences of their actions," according to a statement from their attorney, Gloria Allred. The filming of “Rust” moved to Montana after Hutchins' death under an agreement with her husband, Matthew Hutchins, that made him an executive producer. Baldwin indicted. Prosecutors dismissed an earlier involuntary manslaughter charge against Baldwin after being told the gun he was holding might have been modified before the shooting and malfunctioned. A new analysis of the gun opened the way for prosecutors to reboot the case. A grand jury indicted Baldwin on the same charge in January. The indictment alleges Baldwin caused Hutchins' death - either by negligence or "total disregard or indifference" for safety. If he's convicted, the charge carries a potential prison sentence of up to 18 months. Pathways for prosecution. The indictment offers prosecutors two alternative standards for the charge against Baldwin. One would be based on the negligent use of a firearm. The more recent gun analysis, conducted by Forensic Science Services in Arizona, calls into question Baldwin's version of events. It concluded "the trigger had to be pulled or depressed sufficiently to release the fully cocked or retracted hammer of the evidence revolver." Baldwin's defense. Baldwin's attorneys say Hutchins' death was a terrible tragedy, and prosecutors are misguided in their attempts to secure a conviction against him. Gutierrez-Reed's attorney, Jason Bowles told jurors in her trial that Gutierrez-Reed was being used as a convenient scapegoat for “Rust” producers, including Baldwin. Bowles suggested Baldwin went off-script when he pointed the weapon at Hutchins. Investigators found no video recordings of the shooting. Messages seeking comment from Baldwin's spokesperson and a lawyer were not immediately returned Wednesday.