With its last opinion on the last day of the term, the Supreme Court brought things back to constitutional basics by striking down a state law that punished political speech. Whatever the motivations behind Arizona’s so-called Clean Elections Act, giving a publicly funded candidate more taxpayer-provided money every time his privately funded opponent—or his supporters—have “spoken too much” clearly chills speech. In elections, where there is no effective speech without spending money, matching funds provisions triggered by speech fail First Amendment scrutiny.

And this result should’ve been obvious to the entire Court, not just a five-justice majority, in the wake of the Davis v. FEC “Millionaires’ Amendment” case from 2008. Davis struck down the part of McCain-Feingold in which spending by individually wealthy candidates triggered increased contribution limits for their opponents. If the mere possibility of your opponent getting more money is unconstitutional, then the guarantee that your opponent will get more money—as was the case under the Arizona law—is even more so.

Allowing the government to burden political speech in this fashion not only diminishes the quality of political debate, but ignores the fundamental principle upon which the First Amendment is premised: that the government cannot be trusted to regulate political speech for the public benefit. Moreover, the state cannot condition the exercise of the right to speak on the promotion of a viewpoint contrary to the speaker’s.

Here’s Cato’s brief in the case, Arizona Free Enterprise Club’s Freedom Club PAC v. Bennett.