Senator Ted Cruz (R-TX), the climate science-denying presidential candidate who chairs the Senate Subcommittee on Space, Science, and Competitiveness, convened a December 8 hearing that purported to answer whether the “debate over the magnitude of human impact on earth's climate” is being driven by “data or dogma.” One of Cruz's star witnesses is frequent Rush Limbaugh Show guest host Mark Steyn, whose extreme attacks on a climate scientist appear to be the main reason he was invited to participate.

The most obvious explanation for Steyn's appearance would seem to be that Cruz couldn't find enough scientists who oppose the 97 percent of climate scientists that say human activities are causing climate change, so he had to turn to a talk radio shock jock instead. But the fact that Steyn is "not a scientist" only scratches the surface of why he is unqualified to testify on global warming.

Steyn has a long history of making extreme and scientifically illiterate claims that could give Cruz a run for his money. For instance, Steyn alleged in 2009 that "[t]here has been no global warming this century." In 2010, he declared that “environmentalism is fundamentally anti-human.” Most recently, Steyn was seen proclaiming that Democratic presidential candidate and Vermont Senator Bernie Sanders' remarks describing the link between climate change and terrorism were “insane,” and even imagining terrorists “sawing Bernie Sanders' head off” while Sanders worries about “an emissions trading scheme.” According to Science Blogs' Greg Laden, Steyn also “recently self published a book made up, apparently, of cherry picked quotes and related material in an effort to discredit top climate scientists.”

In addition to his track record of climate denial, Steyn provided another possible explanation for his inclusion at the hearing when he explained why he was invited to a conference held by the climate science-denying Heartland Institute earlier this year, as Energy & Environment recently reported (emphasis added):

Also testifying will be Mark Steyn, the Canadian National Review writer and author of “Climate Change: The Facts” who told attendees at the Heartland Institute's International Conference on Climate Change this summer that his claim to fame is calling fraudulent the well-known “hockey stick” theory that Michael Mann -- a climate scientist at Pennsylvania State University -- has developed. [...] “I've made no useful scientific contribution,” Steyn said at the [Heartland] conference in July. “I've basically only been invited here because ... I'm being sued by the inventor of the global warming hockey stick, Michael Mann.”

Indeed, as Laden observes, "[i]t appears that the Republicans on the Senate science subcommittee are allowing an anti-science Canadian citizen [Steyn] to use the Senate hearing room to argue his side of a civil law suit." As the Union of Concerned Scientists noted, Penn State University climate scientist Michael Mann sued Steyn for defamation after Steyn wrote a 2012 blog post for National Review Online that falsely claimed Mann's "hockey stick" research showing a spike in global warming in the last century was “fraudulent” -- and cited a Competitive Enterprise Institute blog comparing Mann to disgraced Penn State football assistant coach Jerry Sandusky. The CEI blog, by Rand Simberg, asserted that Mann was “the Jerry Sandusky of climate science, except that instead of molesting children, he has molested and tortured data” (that sentence has since been removed). Steyn said of Simberg's accusation: “Not sure I'd have extended that metaphor all the way into the locker-room showers with quite the zeal Mr Simberg does, but he has a point.”

The ongoing lawsuit gets at a broader reason why Steyn may have been invited to appear before the subcommittee: to present his story as supposed proof that dogma trumps data in the climate “debate.” In his prepared remarks to the subcommittee, Steyn said that his own personal “travails” are relevant "[b]ecause too many people within the climate cartel are demanding that dissent from the alleged 'consensus' should be not merely a civil offense but a criminal one - and far too many legislators and bureaucrats are willing to entertain it." He then used that as a jumping off point to dismiss investigations into wrongdoing by Exxon Mobil, alleging that New York attorney general Eric Schneiderman is “su[ing] Exxon for not holding the same views on climate change as the more pliable oil companies have been forced to adopt in public.”

But Steyn's version of events badly misstates the issue. Exxon is not under fire simply for “dissent from the alleged 'consensus',” or for “not holding the same views” on climate science as others. The New York investigation and calls for a federal investigation relate to strong evidence that Exxon knew the science of climate change and then purposely misled stakeholders and the public about the issue.

In the end, this shock jock's trip to Capitol Hill is a notable chapter in the joint efforts of congressional Republicans and conservative media to attack climate scientists and defend the supposed “right” of corporations to intentionally deceive the public about climate change.

So while Steyn freely admits that he is no expert on climate science ( “I am not a climate scientist, but I am an acknowledged expert in the field of musical theatre” ), he was nevertheless one of the five witnesses testifying on the issue before the Senate today. And to give you an even better sense of how far he should be from a Senate hearing, here are some other instances of Steyn talking about issues he is not an expert on, culled from the Media Matters library: