From another comment of mine, the specific relevant passage is on page 7. Copied verbatim - line with a '>' is Stallman quoting another e-mail in the thread.
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> Giuffre was 17 at the time; this makes it __rape__ in the Virgin Islands.
Does it really? I think it is morally absurd to define "rape" in a way that depends on minor details such as which country it was in or whether the victim was 18 years old or 17.
I think the existence of a dispute about that supports my point that the term "sexual assault" is slippery, so we ought to use more concrete terms when accusing anyone.