Wow. Sheriff Dupnik admits he hasn't got a shred of evidence that Loughner even listens to right wing radio or other sources of right wing rhetoric, and yet repeatedly says that he has "no doubt" that this is what caused him to commit mass murder.
Why are so many people on the left so convinced that the "climate of hate" theory is true?
There are three features of this sort of talk that I think are relevant to finding the correct explanation:
1. As the Sheriff's comments suggest, this idea is probably not rooted in concrete evidence. There actually is an academic literature that advances this idea -- it is the basis of "speech codes" and "hate speech laws" -- but as far as I know, none of it ever cites actual, scientific studies that correlate "bad" speech with actual violence.
2. The theory is never applied to liberal, socialist, feminist, or environmentalist rhetoric. When the Unabomber killed 3 people and wounded 23 others, no one said "Boy, these environmentalists had better tone down their rhetoric!" The theory is not really about overheated rhetoric at all. It is about overheated right-wing rhetoric.
3. Though the belief in the theory is no doubt sincere, it seems to me that the avowals of fear are not. Though people like Dupnik are talking about things that are supposed to be scary, they do not actually seem to be frightened. Look at Dupnik's face and listen to his tone of voice. What do you perceive? Me too. Their tone is generally one of scolding, preaching, hectoring, and complaining -- not one of sincere cries of fear. Cong. Giffords famously claimed that Palin's "gunsight" web page put her in danger -- yet on the day she was viciously attacked, she was at an event in front of a Safeway supermarket, completely open to the public and with no security at all. This is not the behavior of someone who feels she is in any danger.
I think this is a very interesting phenomenon, and calls for some sort of special explanation. What is the explanation for this curious behavior? I'll post my answer in the next day or so.
I hope the suspense of waiting is bearable!