The Multiple Hazards of Using Concurring Opinions to Estimate Personality Traits of U.S. Supreme Court Justices

Psychological scholarship on personality is uniting with political science to redefine existing theories. This is clearly the case with research on judicial behavior and the U.S. Supreme Court. But if this new approach is to survive and thrive, it must employ measures equal to the task. We show how the Supreme Court Individual Personality Estimates (SCIPEs), which seek to estimate justices’ personalities by examining their concurring opinions, suffer from a number of critical deficits. Scholars should not employ them. We briefly discuss what kinds of improved personality measures scholars should use instead.