I think this thread is evidence of the fact that's precisely what they ended up doing. A single additional word would have cleared this up:
McCoy: "And the good news is they're not going to prosecute us!"
or
McCoy: "And the good news is they're not going to prosecute her!"
>Shrug< I'm not seeing a few very vocal people in this thread who are misunderstanding the line as representing a great mass confusion on this plot point. "And the good news is, they're not going to prosecute" has a better rhythm without an extra word at the end, and it's always a good idea to have your jokes be as short & punchy as possible. An extra word at the end changes the emphasis of the sentence. The punchline is in the word "prosecute."
And the fact that the very last we see of Valeris is her being held in handcuffs speaks volumes. Movies are about images, and there is
no ambiguity to that image. Contrast it with the ending of a film that came out just two years after TUC, 1993's
The Fugitive. The very last scene is U.S. Marshall Phillip Gerard releasing Dr. Richard Kimble from his handcuffs, and we get this exchange:
GERARD: Let me see those hands, Doctor.
KIMBLE: I thought you didn't care.
GERARD: I don't.
GERARD: Don't tell anybody, okay?
Contrast that with "I didn't kill my wife!" / "I don't care." Yeah, there's still stuff to take care of at the end (that's why they're going away in a squad car), but that scene tells you all you need to know. Gerard now believes that Kimble is innocent, the real bad guys have been caught, and Kimble is at long last going to be all right. The chase is over. We've gone from A to Z.
Or look at the Trek movies. In TUC, Kirk goes from "Let them die" to believing that peace with the Klingons could be a good thing. Spock goes from believing in Valeris and thinking that he knows best to being betrayed & humbled. In TWOK, Kirk goes from "Galloping around the cosmos is a game for the young" to "I feel... young." In TSFS, Kirk goes from believing "The needs of the many outweigh the needs of the few" to sacrificing his son and his ship because the needs of the one outweighed the needs of the many. In ST09, Kirk goes from "the only genius level multiple offender in the Midwest," dreaming of a better life, to saving the Federation and captaining the
Enterprise. You start with your character in one place, and you end with them someplace completely different. A to Z. That's storytelling 101.
If Valeris is beloved & heroic at the beginning of TUC and then forgiven & set free at the end, she has no arc. She's learned nothing and achieved nothing. But going from a valued protege that Spock wants to succeed him on the
Enterprise to a traitor to the Federation - now
THAT'S a story!