Is Campaign Spending a Cause or an Effect? Reexamining the Empirical Foundations of Buckley v. Valeo (1976)

The Supreme Court’s campaign finance jurisprudence rests on a distinction between spending restrictions (generally struck) and contribution restrictions (often upheld). In Buckley v. Valeo (1976), the case originating this distinction, the majority rejected an “anti-distortion” rationale for spending restrictions, claiming that campaign spending is merely an effect of candidate support, not a cause of candidate support. If this claim is true, then removing restrictions on campaign spending should have no discernible causal impacts. This article tests the Buckley majority’s empirical claim using its own ruling, which struck limits on campaign spending in state elections in 26 states. Estimates consistently suggest that the Buckley-induced removal of state limits on campaign spending led to increased Republican vote shares, increased Republican candidate entry, and decreased Democratic candidate entry in state legislative and gubernatorial elections in states affected by the ruling, as well as increased Republican House vote shares and the election of more conservative House incumbents in states both affected by the ruling and holding concurrent federal and state elections. These findings suggest that the rationale for the core distinction in the Supreme Court’s campaign finance jurisprudence has little empirical foundation.