Note...if I use caps, it is for emphasis only, and that I may make my point more clearly.
"I thought murder was a crime in this country no matter what you beleive."
Yes, I've always believed that. But, in criminal law, I reckon there's a thing about 'justifiable' homicide, or 'self defense'. And I know in this state, it is lawful indeed, to use deadly force to protect your life, the life of another, or even in some cases, your property.
But if we lock God into following laws and dictates in respect to just such a scenario as you've outlined, I think we do Him an injustice.
For it is Paul who said, "Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: FOR THE LETTER KILLETH, BUT THE SPIRIT GIVETH LIFE." 2 Cor. 3:6.
In the case you mentioned above, if following the letter of the (Old Testament) law (Thou shalt not kill), the girl will die...and the fact will be that the letter, by not allowing you to deliver her from her murderous father, killed her.
If Jesus were here on earth, in person just as you and I are, what would He have done? I suspect He, being able to work any and all kinds of miracles, would have miraculously delivered the girl (just as He delivered Peter from drowning). But us? We don't generally do miracles that contravene the laws of physics and nature (not that some couldn't, but that it isn't a general thing).
And God, being concerned with righteous judgment over and beyond the law, I believe would expect us to intervene and save the innocent girl's life, even it if came to using deadly force. For it was James who said, "For he shall have judgment without mercy, that hath shewed no mercy; AND MERCY REJOICETH AGAINST JUDGMENT." James 2:13. I believe God would have mercy in this case, with the innocent delivered, and the would-be murderer delivered at the same time, one way or another (dead or alive) to judgment.
But something like this is hard to establish objectively, for any passage of scripture we might use to buttress a particular position, can usually be used to cut both ways, not to mention other passages that deal with the matter from a different light.