Under the Influence

I found myself having a little debate in my head as I read parts of Configurable Culture. I agree on a fundamental level that music influences, reflects, and amplifies the human psyche. Who can argue that music doesn't have a profound effect on us--emotionally, spiritually, socially, or otherwise?
But then I think about how well this would support the conservative censors who claim that Marilyn Manson is the reason why Columbine happened, and about how strongly I disagree with that.
Honestly, I don't really know how to reconcile this. Could it be that I like to think of music as an instrument for positive rather than negative influence? Or do I just reject the use of music as a scapegoat to avoid personal responsibility?