Natural Scientists Advocating Climate Change Policies Undermines Persuasiveness

• In Event: Science, Trust, and Public Opinion

Abstract

For centuries, natural scientists have been conducting research that has implications for public policy. Yet natural science findings rarely dictate specific, optimal policy solutions for societal problems. For example, scientists studying climate change can characterize dangerous possible futures. They can highlight the potential benefits of greenhouse gas emissions reduction. Still, those natural science findings do not point to specific legislative mechanisms or free-market strategies that are best for reducing emissions. Whether to take action and which of various possible legislative strategies are optimal have been matters of vociferous debate, often informed by theories and evidence from the social sciences.
When attempting to contribute positively to policy-making, natural scientists can choose to communicate to the general public simply by (i) describing the natural world as their research illuminates it (e.g., climate change has been happening, caused importantly by human activity), (ii) proposing strategies to ameliorate current or future problems (e.g., advocating reduction of greenhouse gas emissions, (iii) endorsing specific government policies to achieve that amelioration, and (iv) encouraging the public to pressure policy-makers to pursue specific amelioration strategies (e.g., Pielk 2007).
If natural scientists limit their public communications to focus on the findings of their natural science research, they “stay in their lane” by presenting evidence that can inform policy-making without becoming directly involved in the policy-making process, about which their natural science credentials confer them no expertise. Or natural scientists can “cross the line” into another “lane” by advocating particular policy solutions, despite lacking training and expertise in the policy-making or associated political processes.
Although natural scientists might feel that “muzzling” them when it comes to the public policy implications of their natural science findings is unfair and counterproductive and deprives them of the right to participate in politics that all citizens in democracies have, such muzzling might actually enhance the impact of these scientists on exactly the public policy debates that they wish to influence. That is, by “staying in their lane”, natural scientists may avoid appearing to express opinions in areas where they lack expertise and may therefore be more convincing in their assertions regarding natural science.
The research being proposed here will test that hypothesis. We applied psychological theory to explore the effects of crossing the line on the general public’s adoption of the views advocated by natural scientists. One possibility is that the public might welcome natural scientists’ policy recommendations. Another possibility is that crossing the line into the policy arena might be perceived as breaking expertise-imposed limitations and thereby undermine the persuasiveness of natural scientists about natural science.
This paper will report between-subject experiments exploring whether various forms of “crossing the line” into policy advocacy enhance public endorsement of such policies, with or without ascribed policy expertise.
In online surveys, American adults (N=9,822) were randomly assigned to watch various videos of a natural scientist delivering various versions of messages about his scientific credentials and scientific findings and advocacy for policy.
In version 1, the natural scientist said that government should take action on climate change; in versions #2 and #3, he advocated two emissions reduction policies; in versions #4, #5, and #6, he recommended general policies focusing on mitigation, adaptation, or both mitigation and adaptation; and in versions #7, #8, and #9, he said that public policy experts should devise the best policies for mitigation, adaptation, or both mitigation and adaptation, respectively, without advocating specific policies.
Describing natural science findings alone increased people’s belief in those findings and approval of ameliorative policies, and these effects were mediated by increased trust in scientists generally. Second, policy advocacy did not enhance support for the policies when the natural scientist was described as having policy expertise but reduced policy support when the scientist was not.
These findings suggest that natural scientists should not advocate specific policies, because doing so either has no effect or undermines their persuasiveness. And these findings suggest that communicators in the political arena might be most persuasive when the restrict their communications to areas in which they are expert and explicitly defer to others with different expertise to follow-through on the implications.

Authors

• Bo MacInnis, Stanford University

• Jon A. Krosnick, Stanford University