As you may have heard, the Heartland Institute, a right-wing anti-climate-science think tank, has launched a billboard campaign that’s getting widely pilloried on the Web — it compares people who accept climate science as legitimate to Osama Bin Laden, Charles Manson, and the Unabomber.

Now the Heartland Institute has suffered its first major defection in the way of GOP public officials: GOP Rep. James Sensenbrenner of Wisconsin, a leading climate “skeptic,” will be pulling out of an upcoming conference sponsored by the group where he was supposed to speak, his spokesperson confirms to me.

The billboards, which were first reported by the UK Guardian, show the Unabomber or Manson saying: ”I still believe in Global Warming. Do you?” Future billboards may include Bin Laden, reported the Guardian, which referred to the billboards as “possibly one of the most ill-judged poster campaigns in the history of ill-judged poster campaigns.”

The group has a conference set for later this month, and one of the featured speakers is Sensenbrenner. I asked Sensenbrenner’s spokesperson, Amanda Infield, if he’s still participating. She emails:

Congressman Sensenbrenner will not participate in the upcoming Climate Change Conference if the Heartland Institute decides to continue this ad campaign. We have contacted the Heartland Institute and voiced these same concerns to them.

Joe Romm reports that a several major corporations have ended their support for Heartland, but many still continue to bankroll it, and many other prominent voices are expected to speak at Heartland’s conference.

As Andrew Sullivan, writing about the billboards, put it: “In some ways, this is an almost perfect illustration of what has happened to the `right.’ A refusal to acknowledge scientific reality; and a brutalist style of public propaganda that focuses entirely on guilt by the most extreme association.”

Indeed, it’s likely that the pressure will increase, via social media, for these companies and voices to sever their ties with Heartland until they pull the billboards down. As Sensenbrenner has showed by pulling out, there are some positions that are too extreme for “climate skeptical” mainstream Republicans to countenance, such as comparing climate change science believers to mass murderers.


Update: Heartland just announced that they’re pulling the billboard, which they described as an “experiment.”