Alec Baldwin Wins Critical Battle in 'Rust' Case, D.A. Drops Gun Enhancement Charge

The Santa Fe County D.A. has gotta be a little embarrassed today ... dropping a key charge against Alec Baldwin that now means even if convicted he might not spend any time behind bars.

The D.A. dropped the gun enhancement charge in the case ... this after Baldwin's lawyer filed a motion excoriating prosecutors for going after the actor using a law that didn't apply.

As we reported, Baldwin has been charged with involuntary manslaughter in the death of Halyna Hutchins. The D.A. initially tacked on the gun enhancement charge -- i.e., using a gun to commit the crime. Problem is, at the time of the shooting, New Mexico law provided a gun enhancement charge could only apply if the gun was "brandished" -- meaning the gun was displayed with intent to intimidate or injure a person. That's clearly not the case with Baldwin.

For some reason, the D.A. felt Baldwin could be charged with a recent amendment to the gun enhancement law, that doesn't require brandishing. Thing is ... that law was not enacted until 7 months after the shooting.

The D.A. belatedly saw it Baldwin's way and dropped the gun enhancement.

Here's why it matters ... if the gun enhancement charge stuck and Baldwin was convicted, he'd face a minimum of 5 years in prison. Now that it's been 86'd, if Baldwin is convicted of involuntary manslaughter, he'd face up to 18 months behind bars, but the judge could give him less ... or even probation.