Skip ahead to 1:30 for Matthews’s question about “atmospherics,” followed by Dupnik casually asserting that Loughner must have been especially vulnerable to “anger, hate, paranoia, and so forth.” If he has proof of that, he conveniently forgot to mention it. Over to you, Arizona Republic:

Was Dupnik unnecessarily inflammatory? It seemed so. But it came mere hours following a horrific, bloody mass murder. If you weren’t on edge, you weren’t being human. But then, on Sunday, the venting continued anew. And a horrified nation began paying closer attention to the Pima County sheriff.

The world’s eyes, once again, focused on Arizona for the worst of reasons. And Dupnik stood before the cameras interpreting the shootings as politically motivated, despite an increasing weight of evidence depicting the shooting suspect, Jared Loughner, as a mentally ill young man who rambled incoherently about pervasive bad grammar and other apolitical obsessions. Even Dupnik has observed that Loughner had made death threats against others and that they had been investigated by police…

Dupnik took up his cause again on Monday. And, in response, we have to say at last . . . enough. Enough attacks, sheriff. Enough vitriol. It is well past time for the sheriff of Pima County to get a grip on his emotions and remember his duty.

Dupnik needs to recall that he is elected to be a lawman. With each additional comment, the Democratic sheriff of Pima County is revealing his agenda as partisan, and, as such, every bit as recklessly antagonistic as the talk-show hosts and politicians he chooses to decry.

Other county sheriffs in Arizona have now started grumbling about him, even as Dupnik goes around telling people like Olbermann that it’s basically his legal duty to float half-witted psychological theories about how Sarah Palin’s fundraising literature may or may not affect the mind of someone who’s seriously deranged. And after days of gratuitously inflaming an already highly inflamed situation, what does he get? Why, a thank-you call from the president. Of course.

If you’re looking for a thoughtful psychological profile of mass murderers, if only to cleanse your mental palate of what you’re about to see, Ronald Bailey has a piece at Reason that’s worth your time. Nutshell version: “[U]nmarried, childless, unemployed white male with no readily discernible political motivations who just experienced a major life failure.” To follow on that thought, I was wondering last night after writing this post about Loughner’s mental state, is there any actual scientific reason to believe that deranged people are more susceptible to being incited by heated political rhetoric? Intuitively, it makes sense: An already agitated mind is apt to turn in extreme, unpredictable directions under further agitation. But as I say, that’s intuition, not science. Maybe some agitated minds would find political bombast too intense to stand, like turning a sun lamp on someone whose skin is hypersensitive to light. Or maybe, even within the category of deranged people, there’s some room for personal tastes and preferences when it comes to persuasion. Maybe having Glenn Beck scream at Loughner about Woodrow Wilson would increase the risk of him killing someone — or maybe it would just really freak him out. Maybe, per Loughner’s bent towards math and pseudo-philosophy, he’d be more easily programmed to kill by calmly feeding him “logical” conclusions (e.g., “all liberals/conservatives are racist, society is better off without racists, ergo society is better off without liberals/conservatives”). It stands to reason that pathologically erratic personalities will respond to stimuli in unpredictable ways — and yet here we have Dupnik, blithely insisting that, no, surely, surely, Jesse Kelly’s campaign events played some role in this. It takes a Supercop to read minds in ways that not even psychiatrists are able to, my friends.

Be sure to watch the whole clip for Matthews’s assertion that when Mark Penn said a new Oklahoma City might help Obama out politically, he only meant that it would give O a chance to play peacemaker. That’s simply not true: You can watch the original clip at Mediaite, with Penn talking about Obama using a tragedy like OKC to “reconnect” with voters after the midterm landslide. Even lefty Tommy Christopher was horrified by it.

Update: Speaking of Loughner and deranged minds, cops have revealed the text of another letter found in the safe in his house alongside the ones reading “I planned ahead,” “My assassination,” and “Giffords.” The text: “Die, bitch.”

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