Evaluating Evidentiary Standards in the Realm of Citizen Policy Evaluation

This paper explores individual-level standards of evidence in the political domain. We define "standard of evidence" as the threshold at which information collection transitions to decision-making. In particular, we aim to understand what evidentiary standards voters rely on when they evaluate the effectiveness of legislation passed by their in-party vs. the out-party. Our empirical investigation is based on original survey data collected in August 2023 in the United States and it provides two main findings. First, both Democrats and Republicans are more likely to apply looser evidentiary standards for policies passed by their own party. This implies that voters in the U.S. consider their own party's policies to be more efficacious in part because they have adopted lower standards for perceived policy success. Second, we find that policy authorship also influences the type of evidence that people rely on when they evaluate policy. Our models suggest that individuals are (1) less likely to consider long time horizons and (2) less likely to reflect on alternative causes when they evaluate the efficacy of a bipartisan economic policy compared to one authored by only one major party.