They certainly don't care what economists think. Photographer: John Moore/Getty Images
They certainly don't care what economists think. Photographer: John Moore/Getty Images

In his 2014 State of the Union address, President Barack Obama tried to attract support for one of his highest priorities when he said, “Independent economists say immigration reform will grow our economy and shrink our deficits.” He’s right. Economists disagree about a lot of things, but on behalf of immigration reform, there is a professional consensus that cuts across the usual political divisions. Why, then, has reform stalled in Congress?

Obama's strategy assumed that people care what economists think. And in many contexts, they do. On largely technical issues -- such as whether it would be a good idea to return to the gold standard -- Americans pay attention to the consensus within the economics profession, as recent research by Christopher Johnston and Andrew Ballard of Duke University shows. Especially if people begin with a high level of uncertainty about their own opinion, the views of economic experts can convince them to change it.

Swerving Path to Citizenship

But on issues with heavy symbolic dimensions, where emotions tend to run high, economists have far less influence, even if they speak with one voice. Would Americans benefit from more trade with China? Most economists say yes, but only a minority of Americans agrees -- even after they learn what economists think.

On immigration, the evidence is more striking still. Economists, Johnston and Ballard note, concur with the following statement: “The average U.S. citizen would be better off if a larger number of highly educated foreign workers were legally allowed to immigrate to the U.S. each year.” But here as well, only a minority of Americans agrees. And when people learn what professional economists think, they do not shift toward the consensus. On the contrary, there is an apparent backfire effect: The percentage of respondents who disagree with the statement rises.

The backfire effect has been found in other contexts as well. Suppose that people strongly believe that the Affordable Care Act creates death panels, then hear from an apparently independent source that it does not. Evidence suggests that their original belief might well become even stronger. One reason is people's natural tendency to reduce cognitive dissonance; they fend off any challenge to convictions to which they are deeply committed.

When the challenge comes from economists, there’s another problem: Americans do not much trust the economics profession. Johnston and Ballard found that just 15 percent think public officials should rely on economists “a great deal,” and 37 percent think officials should rely on economists “only a little” or “not at all.” (Interestingly, strongly left-leaning people are significantly more trusting of economists than strongly right-leaning people are.) On the issue of immigration, when people who oppose increasing it are informed of the economists' consensus, their level of trust falls further -- a demonstration of what social scientists call “motivated skepticism.”

So drawing attention to what economists think is not the best way to promote immigration reform. It would be far more effective to provide concrete evidence of the benefits of such reform -- ideally from people the skeptics find credible.

To contact the writer of this article: Cass R. Sunstein at csunstei@law.harvard.edu.

To contact the editor responsible for this article: Mary Duenwald at mduenwald@bloomberg.net.