EPA’s new science adviser will bolster objectivity and transparency

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EPA Administrator Scott Pruitt has appointed respected decision scientist Louis Anthony Cox, Ph.D. as chairman of EPA’s Clean Air Scientific Advisory Committee (CASAC).

Most Americans have probably never heard of CASAC, a seven-member committee Congress created 40 years ago “to provide advice and recommendations to EPA” on air quality science. For most of its tenure, it kept a low profile, offering its scientific expertise to EPA administrators about the strength of evidence used to support air quality regulations. In recent years, however, its members have strayed from their mandate to advise on scientific questions and become vociferous advocates for (or opponents of) certain policies.

{mosads}This has led to accusations of politicized science, not only eroding trust and transparency in the regulatory process, but reducing the effectiveness of environmental regulations. The appointment of Cox is an important first step in returning the committee to its original scientific mission and may help restore scientific integrity and political accountability that are essential to effective environmental policy.


Cox has a reputation as an independent thinker and is a leading expert in the statistical analysis of risk and uncertainty. He is editor-in-chief of the respected journal, Risk Analysis, president of Cox Associates, and has served as honorary full professor at the University of Colorado, teaching computational statistics, epidemiology and decision and risk analysis. He holds doctorate and master’s degrees in risk analysis and operations research from MIT.

At CASAC’s helm, Cox can help EPA understand causal relationships between air emissions and public health. Without that core scientific foundation, estimates of the impact of regulatory policies are little more than guesswork, and environmental regulations will struggle to achieve their intended goals.

Although “correlation does not imply causation,” EPA and CASAC have in recent years rationalized costly mandates with questionable inferences about whether small changes in exposure cause changes in health risks. Two former Obama officials and their colleague (Dominici, Greenstone and Sunstein) cautioned in the journal Science that EPA’s “associational approaches to inferring causal relations can be highly sensitive to the choice of the statistical model.” Exposures can appear benign, irrelevant or highly risky, depending on modeling assumptions.

Cox brings rigorous risk analysis expertise to the science questions EPA must face to more effectively target — and reduce — real public health risks. Risk analysis can help policymakers and others understand what is known and not known about environmental hazards. Rather than reading statistical tea leaves, causal risk analyses would present policy officials with objective scientific evidence and information on key uncertainties necessary to inform policy decisions.

CASAC has an important role to play in providing objective scientific input to agency decision makers. However, experts warn that science advisors should not try “to answer questions that go beyond matters of scientific judgment.” In recent years, CASAC has increasingly done just that.

A Congressional Research Service report found that for most of its history, CASAC focused on examining whether the scientific basis prepared by EPA staff was adequate for making regulatory decisions. Lately, however, CASAC has gone way beyond evaluating the science and instead has taken an advocacy role based on members’ preferred policy outcomes.

This may not seem like a problem. After all, we want air quality standards to be “based on science.” But many policy questions are not answerable by science alone, as Alvin Weinberg observed in his landmark 1972 article, “Science and Trans-Science.” What he called “trans-scientific questions” are not pure science and their answers depend on assumptions, judgments and rules of thumb. Weinberg said, “the scientist cannot provide definite answers to trans-scientific questions any more than can the lawyer, the politician or a member of the lay public,” but “he does have one crucially important role: to make clear where science ends and trans-science begins.”

Under Cox’s leadership, CASAC may better serve that role for policy officials by highlighting what science can and cannot say about efforts to reduce environmental risks. Causal risk analysis avoids some of the inevitable human biases imbedded in the associational methods EPA has relied on in recent years. With his expertise, Cox can return CASAC to its important statutory mission of advising policymakers and the public on what the science shows, while leaving the policy advocacy to others.

Susan E. Dudley directs the George Washington University Regulatory Studies Center and is a distinguished professor of practice in the Trachtenberg School of Public Policy and Public Affairs. She served as administrator of the Office of Information and Regulatory Affairs from 2007 to 2009.

Tags Environmental policy in the United States Environmental Protection Agency Scott Pruitt Scott Pruitt Susan E. Dudley
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