A prosecutor told jurors that Alec Baldwin "violated the cardinal rules of firearm safety" in opening statements Wednesday at his trial for involuntary manslaughter.

"The evidence will show that someone who played make believe with a real gun and violated the cardinal rules of firearm safety is the defendant, Alexander Baldwin," special prosecutor Erlinda Ocampo Johnson said.

She emphasized that the set of the film Rust, where cinematographer Halyna Hutchins, "a vibrant 42-year-old rising star," was shot and killed, was a workplace.

"The evidence will show that like in many workplaces, there are people who act in a reckless manner and place other people in danger," Johnson said. "That, you will hear, is the defendant."

Johnson walked the jurors through the events leading up to the Oct. 21, 2021 shooting. She said on that day, Baldwin declined multiple opportunities for standard safety checks before the rehearsal and instead "did his own thing" with the revolver at the rehearsal where Hutchins was killed.

WATCH | There were 'fundamental safety violations' on Rust set, former prosecutor says: 

'Fundamental safety violations' on Rust set, says former prosecutor

Matt Long, a former prosecutor specializing in gun and violent crime, says that even though Alec Baldwin could face up to 18 months in prison for his role in the fatal shooting on the Rust film set, 'lifelong consequences' could follow the actor.

"He cocks the hammer, points it straight at Miss Hutchins, and fires that gun, sending that live bullet right into Miss Hutchins body," Johnson said.

Johnson is a relative newcomer to the case, appointed in late April by the Santa Fe district attorney's office.

The trial will delve into the confluence of gun safety, high-wattage celebrity and a low-budget Western movie on the remote ranch set.

The 16 jurors — 11 women and five men — come from a region with strong currents of gun ownership and safety informed by backcountry hunting. Four of the jurors will be deemed alternates while the other 12 deliberate once they get the case.

The shooting death of cinematographer Hutchins nearly three years ago sent shock waves through the film industry and led to one felony charge against Baldwin that could result in up to 18 months in prison.

Baldwin has pleaded not guilty. He entered the courtroom with a disposable coffee cup in his hand. His wife Hilaria Baldwin and brother, Stephen Baldwin, were seated close by in the audience, among relatives and friends of the defendant.

He sat surrounded by his lawyers, wearing a dark blue suit in the downtown Santa Fe courthouse a short drive from the movie-ranch setting of scenes from Rust.

Baldwin has claimed the gun fired accidentally after he followed instructions to point it toward Hutchins, who was behind the camera. Unaware that it was loaded with a live round, he said he pulled back the hammer — not the trigger — and it fired.

Prosecutors have said they'll present evidence that Baldwin went "off script" and failed to follow basic industry standards for firearms safety when he pointed the firearm at Hutchins on Oct. 21, 2021.

Armourer's charges

Baldwin, the star of Beetlejuice, Glengarry Glen Ross and 30 Rock,  has been a household name as an actor and public personality for more than three decades.

In court filings, defence attorneys have highlighted that the armourer, Hannah Gutierrez-Reed, already has been found responsible for the shooting, along with testimony that the gun had been checked by an assistant director before it was handed to Baldwin — and that the shooting was incomprehensible and shocking to the entire movie crew because of their belief that there was no live ammunition on set.

Prosecutors have two alternative standards for proving the charge. One is based on the negligent use of a firearm. The other is proving beyond a reasonable doubt that Baldwin acted with total disregard or indifference for the safety of others.

Testimony at trial will delve into shortcomings in a final safety check of the gun before Baldwin began rehearsing with it, as well as the mechanics of the weapon and whether it could have fired without a trigger pull. The live bullet that killed Hutchins also wounded director Joel Souza.