The La Jolla Papers: Lowering the Scientific Standard of Proof

Four years ago, two dozen nationally recognized environmental activists, academics and trial lawyers met in La Jolla, CA to explore “whether we might use the lessons from tobacco-related education, laws, and litigation to address climate change.” After that meeting, they published an extremely candid 36-page report that described what they discussed behind closed doors.

Following is the latest installment of highlights from that report, which we are calling The La Jolla Papers.

Apparently, there was some dissension in the ranks about “the appropriate standard of evidence required when attributing specific environmental phenomena to global warming and establishing the culpability of carbon emitters and producers.” As the report states:

Several of the climate scientists at the meeting addressed the scientific challenges involved in attributing specific environmental effects to anthropogenic climate change …Myles Allen [a climate scientist at Oxford University] noted that while scientists can accurately speak about increases in average global temperature, such large-scale temperature measurements are difficult to link to specific individuals.

Claudia Tebaldi, a climate scientist at Climate Central, emphasized the problem of confounding factors: “If you want to have statistically significant results about what has already happened [on the health impacts of climate change],” she said, “we are far from being able to say anything definitive because the signal is so often overwhelmed by noise.”

As a result, some of the participants recommended using a different standard of evidence when speaking with the public about climate change.

As [conference organizer Naomi Oreskes] explained, “When we take these things to the public, I think we often make a category error. We take a standard of evidence applied internally to science and use it externally. That’s part of why it is so hard to communicate to the public.”

Oreskes pointed out that the “95 percent proof rule” widely accepted among scientists might not be appropriate in this application. That standard of proof, she said, “is not the Eleventh Commandment. There is nothing in nature that taught us that 95 percent is needed. That is a social convention …

Dick Ayres agreed, emphasizing that, “Too high a standard of proof increases the burden on those who seek to protect public health.”

That did not sit well with some of the scientists in the room, who “took issue with the idea that they ought to apply different standards of proof to their work.”

Claudia Tebaldi, for instance, responded, “As a scientist I need to have two different standards? I don’t see that. I am not convinced that I should lower my standards of skepticism when I talk to the public. As a scientist I give you the probability. It is not my job to change my paper if the consequences are so bad. That is the job of a policy maker working with my results.”

Obviously, this difference of opinion in no way suggested that either party doubted the existence of anthropogenic climate change. But it does demonstrate how far the La Jolla activists would go to implicate Exxon in “crimes” that they simply made up.