Conventional and Alternative Perspectives on Supreme Court Legitimacy: A Systematic Review of Experimental Evidence

A prominent conventional theory holds that attitudes about the U.S. Supreme Court’s legitimacy reflect ingrained institutional commitments that are robust against most disagreeable decisions. However, an alternative theoretical framework suggests that legitimacy attitudes are more dynamic and responsive to Supreme Court decisions and political context. We conduct a systematic review of 55 discrete experiments drawn from 39 published articles. The large majority find that low-dose treatments significantly move expressions of Supreme Court legitimacy, typically conditional on subjects’ partisan, ideological, or affective orientations. The cumulative weight of experimental evidence indicates that diffuse support is more fragile than conventional legitimacy theory predicts.