With all kindness, you should look more into that book. I believe it was the New York Times review that quite rightly pointed out that the "acclaimed writer" didn't actually speak to prosecutors, investigators, or the University. He interviewed and spoke with only one side of the equation, and then read some police reports that were public in order to understand the investigation.
He also waited until very late in his book to quietly insert the sentence stating that Missoula and the U of M were actually at or below the national average for sexual assaults, and that this was a national epidemic among colleges rather than something endemic to the U of M. By the time anyone got to it, if they got to the end of the book, they had read a couple hundred pages framing the U of M and the local police as the worst actors in the country around sexual assault.
That book was a joke, an it did an awful lot of damage.
