Alec Baldwin 'Rust' Judge Blasts Prosecution After Case Dismissal

The judge in Alec Baldwin 's manslaughter case in New Mexico is ripping prosecutors for misconduct, which she says prevented the actor from preparing his defense.

In new docs, obtained by TMZ, the judge who dismissed the case against Alec says the prosecution "intentionally and deliberately" withheld evidence from Baldwin's legal team ... namely, live ammunition found on the "Rust" movie set matching the live bullet that killed Halyna Hutchins .

Remember ... during the trial, police investigator Marissa Poppell testified her superiors instructed her to create a report documenting that police had received ammunition and to file it under a different case number than the "Rust" case ... so it wouldn't be visible to the defense.

District Court Judge Mary Marlowe Sommer dressed down the prosecution in her final written order ... saying their "willful and deliberate misconduct" gave her no choice but to dismiss the case .

The judge took another shot at prosecutors for "egregious discovery violations constituting misconduct and false testimony elicited during trial."

Alec's case was dismissed last month and he's now taking steps to sue Santa Fe Sheriff Adan Mendoza and special prosecutor Kari Morrissey , who is taking the brunt of the judge's wrath here.

In the meantime, Alec is back in New York filming his new reality TV show with his family.