Hannah Gutierrez-Reed, the head armorer on the film set for the movie Rust, appeared virtually for the court hearing.
Ms Gutierrez-Reed and Alec Baldwin were both charged with two counts of involuntary manslaughter over the death of Halyna Hutchins on set.
The charges came after an investigation into the on-set shooting, which fatally injured the Ukrainian cinematographer.
Ms Gutierrez-Reed is the daughter of Thell Reed, another long-time film industry armorer, and only had a handful of credits to her name prior to Rust.
According to a police search warrant, obtained by the Associated Press, Gutierrez-Reed laid three guns onto a cart including the .45 revolver that contained live ammunition.
Investigator Robert Shilling alleged Ms Gutierrez-Reed's "deviation from known standards, practice and protocol directly caused the fatal death of Hutchins."
According to Shilling, Mr Baldwin was not given proper firearm training or was corrected on "dangerous" safety violations.
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