I think it's Rachel in 17, when they're saving that guy from suicide. And yeah, I was thinking of the NH license plates too, and I think there's one part in 6 when Marco says something to the effect of 'We all agreed: better die than become a Controller.' (Although, the Animorphs are a special case, considering they basically *have* to kill themselves for the good of humanity so their secrets don't get out, regardless of value-of-life issues).

Oh, I don't know that they actually *do* use that as their justification over utilitarian calculus. I mean, it's not like they go around killing every Controller they know to free them from the Yeerks, which would be the logical endpoint of 'free or dead' logic expanded universally. It's the way they hold up this sort of attitude toward infestation as the ideal that sort of bugs me (i.e., all the characters were supposed to admire feel this way.) And it's been so long since I read the final arc.