Rose literally had the keys to Chris' freedom...She dressed it up, lured him in, giving off the illusion of inclusion and progression (while telling "white lies"), only to swiftly and affirmatively deny such a freedom...
Remember when she told Chris' her dad is the type to say he'd vote for Obama's "third term" and insisted he wasn't racist?
Remember when Chris let her know he gotta dip and she said that "they're racists" as a means to show solidarity with Chris' decision to leave?
So you're parents aren't racist but all of their friends are??
"White lies".
Peep how Chris' instincts at the party kicked into overdrive and he confided in the enemy (Rose) who introduced him to the hostile environment. He knew very well he would come off as paranoid but he still said his peace about it (like how black folks have BEEN talking about the injustices that have affected us over numerous generations). He innately knew this situation wasn't right...But, like most of us learn, the wheels are already in motion and there was nothing more he could negotiate...
He ended up having to resort to unapologetic, unrivaled, and unbridled rampages JUST to survive and grasp a piece of freedom, even if the freedom is short-lived...(IE..."Rioting)..