Hannah Gutierrez-Reed, the Rust armorer who was convicted of involuntary manslaughter earlier this year, is seeking to undo her conviction after a judge dismissed the same charge against Alec Baldwin last week.

In stunning proceedings on Friday, the New Mexico judge Mary Marlowe Sommer ruled prosecutors in the case against Baldwin over the fatal on-set shooting of cinematographer Halyna Hutchins had intentionally withheld evidence that could have been favorable to the actor. The evidence, which related to how live rounds of ammunition ended up on the film set, might have been exculpatory for Gutierrez-Reed, her defense argued in a court filing on Tuesday.

Prosecutors have said that Gutierrez-Reed was the source of the live bullet brought on to set, but the new evidence raises questions about that assertion. In March a man brought a box of ammunition into the Santa Fe county sheriff’s office that he said came from the film’s prop supplier and matched the ammunition that killed the cinematographer in October 2021.

The state said that it had no “evidentiary value” and did not include the evidence in the Rust file, meaning attorneys for Baldwin and Gutierrez-Reed did not have access to it. Sommer dismissed Baldwin’s case with prejudice putting an end to the case permanently.

“This court stated on July 12 that the integrity of the judicial system demanded that the court dismiss Mr Baldwin’s case with prejudice,” said defense attorney Jason Bowles in the new court filing. “How can it be any different with Ms Gutierrez-Reed’s case, with this proven litany of serious discovery abuses?”

Kari Morrissey, the special prosecutor in both cases, said she would file a written response in court next week.

The development in Gutierrez-Reed’s case comes just days the case against Baldwin fell apart in what legal observers described as a “botched prosecution”.

The actor was charged with involuntary manslaughter in the death of Hutchins, who was killed in October 2021. The Rust crew was rehearsing at the Bonanza Creek Ranch, a popular movie set about 30 minutes from Santa Fe, when a gun Baldwin was holding fired a single round of live ammunition, striking Hutchins and the director, Joel Souza.

Prosecutors argued that Baldwin was a reckless and arrogant actor who repeatedly mishandled firearms on set, breaking the “cardinal rules of firearm safety”. His defense countered that he was failed by the crew members who were responsible for overseeing weapons and safety on set, and was unfairly targeted by the state.

The case against him unraveled in a matter of hours on Friday as a witness testified that Morrissey was directly involved in a decision to keep the evidence separate from the Rust case, another special prosecutor suddenly resigned in the middle of the day, and Morrissey called herself to the stand. Morrissey said she was not aware that the evidence would not be included in the Rust case file, and that Troy Teske, the man who came forward with the ammunition, was a friend of Gutierrez-Reed’s father.

Sommer had described the state’s actions as “intentional and deliberate”. “There is no way for the court to right this wrong,” she said before dismissing the case.

Gutierrez-Reed is serving the maximum 18-month penalty in a New Mexico prison following her March trial, and had already sought to appeal the involuntary manslaughter conviction.

Prosecutors blamed Gutierrez-Reed for unknowingly bringing live ammunition on to the Rust set and said she showed an “astonishing lack of diligence” with gun safety. “She was negligent, she was careless, she was thoughtless,” Morrissey said in the trial’s closing statements.

David Halls, the film’s first assistant director who was in charge of safety on set, pleaded no contest last year to a charge of negligent use of a deadly weapon.