Cinematographer Halyna Hutchins died from her injuries after being hit by a live round fired from a gun Baldwin was holding during a rehearsal in New Mexico in 2021.
Baldwin, the lead actor and a producer on "Rust," is awaiting his own manslaughter trial at the same Santa Fe court. He has pleaded not guilty and insisted he did not pull the trigger, saying that as an actor, he should have been able to rely on the professionals around him.
But the Hollywood A-lister was at the heart of arguments made by the defense for armorer Hannah Gutierrez, who was responsible for weapons on set and is the first person to go on trial over the tragedy.
"Mr Baldwin, one of the lead producers, head actor on the movie -- he really controlled the set -- you're going to hear that he violated some of the most basic gun safety rules you can ever learn," said defense lawyer Jason Bowles.
"He violated all of those. It wasn't Miss Gutierrez-Reed. It was Mr Baldwin."
Gutierrez, also known as Hannah Gutierrez-Reed, has denied the involuntary manslaughter charges against her.
The prosecution had opened its case by painting a picture of Gutierrez as consistently "sloppy and unprofessional."
"The evidence will show that the defendant treated the safety protocols as if they were optional, rather than that people's lives counted on her doing her job correctly," said prosecutor Jason Lewis.
One of the key questions surrounding the death of Hutchins is how a live bullet found its way onto set and into Baldwin's gun.
Prosecutors showed a photo of Gutierrez that they said showed a live round in a case resting on her lap more than a week before the incident.
"This means that the live ammunition could not have been... supplied by somebody other than Miss Gutierrez," said Lewis.
But defense lawyer Bowles disputed the evidence, arguing that it is not possible to distinguish a live round from a dummy round purely on the evidence of photos.
- 'Scapegoat' -
The trial is the latest attempt to hold someone accountable for an on-set tragedy that sent shockwaves through Hollywood and led to calls for a tightening of the rules around the use of firearms in movies.
Arguing for the defense, Bowles pointed to alleged gaps in evidence collected by police investigating the incident, and said the movie's producers wanted to make Gutierrez a "scapegoat."
He said Gutierrez had been tasked with two jobs -- as both a props assistant and an armorer.
She had been performing tasks like rolling "cowboy cigarettes" instead of being allowed to spend time on weapons safety, he told jurors
Evidence would show that having "a part-time armorer" on a film with so many weapons was "a terrible idea, but that's what they did," said Bowles.
Bowles added: "The primary thing here was 'rush, get this done, so we get the money.' And that's all on production. And Mr. Baldwin is one of the primary producers."
The Gutierrez trial is expected to last two weeks. Baldwin could appear in court for his own trial within months.
Criminal charges against Baldwin have encountered a number of setbacks.
Initial involuntary manslaughter charges were dropped in April last year, due to what prosecutors called "new facts" that demanded "further investigation and forensic analysis."
That led to the empaneling of a grand jury, which late last year handed down new involuntary manslaughter charges.
