New Working Paper: Why Do Members of Congress Support Agricultural Protection?

That’s the title of my latest working paper (here and there), written with my Duke colleague Nick Carnes. Just in time for the latest farm bill debacle, here is the abstract:

It seems paradoxical that developed countries continue subsidizing agriculture even though their agricultural sectors have been declining in relative importance since the middle of the 20th century. What drives support for agricultural protection in developed countries? We answer this question by testing three competing hypotheses about what drives support for agricultural protection in the US: (i) legislator preferences, (ii) electoral incentives, or (iii) lobbying. Using data on the roll call votes of the members of the 106th through the 110th Congresses (1999-2009) and the scores given to each legislator by the Farm Bureau, our findings suggest electoral incentives explain a great deal of the variation in support for agricultural protection, but that legislator preferences and lobbying play a role, too. Moreover, legislator preferences and electoral incentives appear to be substitutes for one another. Why does Congress support agricultural protection? Because many members have electoral incentives to — and because many of those who do not still have other personal or strategic interests at stake.

Thanks to the data Nick assembled for his dissertation (which is the topic of his forthcoming book White-Collar Government: The Hidden Role of Class in Economic Policy Making), we know whether legislators have spent any time working as farm owners or farm managers, and we use that as a proxy for their preferences for agricultural protection.

We combine this with how much money the same legislators have received from agricultural political action committees and with the proportion of their constituents who work in agriculture to look at those legislators’ roll call votes on the 2002 and 2008 farm bills as well as with the scores they are given by the Farm Bureau.

This allows us to study whether support for agricultural protection (i.e., tariffs and quotas on agricultural imports, farm subsidies, etc.) is driven by

  1. Whether legislators have a personal preference for agricultural protection
  2. How much money they receive from the agricultural lobby, or
  3. Whether their constituents have a preference for agricultural protection.

Although many people often assume that support for agriculture is driven by the agricultural lobby, we find that reality is a bit more subtle. Indeed, not only do we find that support for agriculture is largely driven by the electoral incentives of legislators, we also find that any mono-causal explanation for what drives support for agricultural protection would be mistaken.

This is a working paper, so I should add the caveat that our findings have not yet been through the peer-review process. And of course, comments on our work would be most welcome.

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  1. Chris

    I had previously just assumed that lobbying had been the influence for this system of subsidies that makes no sense. I also considered the idea that they treated the farms as a national security industry like they do the steel industry. Electoral incentives makes perfect sense too and i had never even given that a thought. Thanks for the review and I look forward to reading the working paper.

  2. Marc F. Bellemare

    Thanks for reading and commenting, Chris. I was also surprised by the result that lobbying didn’t explain everything. What is even more surprising, when you read the paper, is the marginal impact of electoral incentives. For an increase of one percentage point in the proportion of voters who are farmers, you get an increase of about 40% in the likelihood a legislator will vote pro-agriculture. If that sounds massive, it is, and it is because 99% of legislators have less than 5% of farmers among their voters, so a 1-point increase in the proportion of farmers means they go from, like, 0.5 to 1.5% of farmers in their district. It kind of reminds me how how really small-likelihood events induce extreme behavior in Kahneman and Tversky’s (1979) prospect theory paper.