Where Broockman, Kalla and Westwood differ is with those who take the growing partisan hostility argument a step further, to contend that “if citizens were less affectively polarized, they would be less likely to endorse norm violations, overlook co-partisan politicians’ shortcomings, oppose compromise, adopt their party’s views, or misperceive economic conditions.”

“We find no evidence that an exogenous decrease in affective polarization causes a downstream decrease in opposition to democratic norms,” Broockman and his co-authors write, adding: “We investigate the causal effects of affective polarization on a variety of downstream outcomes,” in five political domains, “electoral accountability (measured by both levels of party loyalty and how individuals react to information about their actual representatives), adopting one’s party’s policy positions, support for legislative bipartisanship, support for democratic norms, and perceptions of objective conditions.”