My best information is that the book Mind Hunter was NOT in the Ramsey house - that MikeKane was lying when he told John it was - and that was perfectly legal. It is a police tactic to get a response.
From the 1998 interview:
MIKE KANE: Okay. What about "Mind Hunter", John Douglas's book was there, was in the house, had you purchased that?
JOHN RAMSEY: No. It was there in '96? Interesting.
MIKE KANE: Why's that interesting?
JOHN RAMSEY: I never never heard of John Douglas or that book before.
That interview took place before John realized just what lengths the cops would go to to get information they might twist their way - - after all, now it was ON THE RECORD that the book was in the house - - misinformation, but still on the record.
By the 2000 interview, John was wiser and when told there were fibers on JonBenet's genitals from John's sweater, he was NOT so polite - - he called Kane a liar.
It is interesting to see how things changed over time.