In February, Chief Justice John Roberts touted his commitment to free speech, declaring: “I think I’m probably the most aggressive defender of the First Amendment on the court now.”

On Thursday, he authorized one of the most effective and widespread attacks on free speech today, prohibiting federal courts from reining in partisan gerrymanders. Roberts’ decision in Rucho v. Common Cause will have a devastating impact on freedom of expression in the United States, allowing lawmakers to punish voters for their political views by diluting their votes. It is the court’s most disastrous betrayal of the First Amendment in recent memory.

Rucho posed a simple question: Can federal courts place limits on partisan gerrymandering? The answer should be obvious, for two simple reasons. First, these gerrymanders impose grave constitutional harm on citizens. Second, they are not at all difficult for courts to remedy.

There is nothing uniquely challenging about measuring and fixing partisan gerrymanders, as multiple lower courts have already demonstrated. The task falls squarely within the court’s duty to protect Americans’ constitutional rights—indeed, to safeguard the most important right, an ability to participate equally in self-governance.

Yet Roberts, joined by the remaining conservatives, declared otherwise in a 5–4 decision. He insisted that partisan gerrymanders “present political questions beyond the reach of the federal courts.” To limit this practice, Roberts wrote, would be to expand “judicial authority … into one of the most intensely partisan aspects of American political life.” And he wrote that federal courts are ill-suited to decide when partisan gerrymandering “goes too far,” as they lack a standard by which to measure a party’s illegitimate entrenchment of political power.

To reach this conclusion, Roberts shrugged off the serious constitutional injuries inflicted by political redistricting. Most notably, he dismissed the plaintiffs’ theory that extreme partisan gerrymandering violates the First Amendment. There are, Roberts wrote, “no restrictions on speech, association, or any other First Amendment activities in the districting plans at issue. The plaintiffs are free to engage in those activities no matter what the effect of a plan may be on their district.” He scoffed at the putative “burden” that gerrymandering placed on the plaintiffs, citing “slight anecdotal evidence” that the minority party had “difficulty drumming up volunteers and enthusiasm.” This alone, Roberts suggested, did not prove a First Amendment infringement.

Unless the chief justice failed to grasp the plaintiffs’ actual theory, he must know this passage is incredibly misleading. The plaintiffs here argued, correctly, that partisan gerrymandering imposes a flagrant and immediate burden on First Amendment rights. It isn’t just about “drumming up volunteers”—it’s about lawmakers penalizing voters on the basis of their political expression and association. Take North Carolina, where Republican legislators intentionally diluted the votes of citizens who expressed support for the Democratic Party. In virtually any other context, this action would constitute viewpoint discrimination, a cardinal sin under the First Amendment. Why doesn’t it here?

Roberts seems to believe that this viewpoint discrimination is OK because it creates “no restrictions” on expression. If that’s true, I am not sure how Roberts can justify his opinion in 2011’s Arizona Free Enterprise v. Bennett, a 5–4 decision striking down a key component of Arizona’s publicly financed elections. Under the law, Arizona provided funds to publicly financed candidates that roughly matched the amount spent by their opponents. The goal was to create competitive races by ensuring that all candidates had sufficient resources to campaign.

Kagan pinpointed exactly where Roberts went so awry.

Arizona’s law created “no restrictions” on expression and certainly didn’t penalize speech on the basis of viewpoint. But Roberts and the conservative justices struck it down anyway, writing that it “substantially burdens the speech of privately financed candidates” by frightening them into spending less. Really? According to Roberts, a law designed to increase political speech by helping more candidates participate in elections “substantially burdens protected political speech” because it dissuades big donors from writing bigger checks. To Justice Elena Kagan, writing in dissent, that was pure madness. “The system discriminated against no ideas and prevented no speech,” she wrote. To the contrary, it plainly furthered “First Amendment values.”

It is difficult to understand a theory of the First Amendment that permits partisan gerrymandering (in part because it imposes “no restrictions” on voters’ expression) while forbidding a matching-fund campaign finance scheme (because it “burdens” big donors’ speech). Roberts’ decisions in Rucho and Arizona Free Enterprise cannot be squared. The only plausible explanation is that the chief justice values the expression of high-dollar donors more than he values the expression of voters. “There is no right more basic in our democracy than the right to participate in electing our political leaders,” Roberts wrote in another decision striking down campaign finance restrictions. Apparently, that right applies with greater force to billionaires writing checks than it does to voters casting ballots.

This vision of democracy, and the role that free expression plays in the political process, is beyond cynical. It elevates the speech of donors above everyday citizens in the hierarchy of First Amendment values. In Rucho, Roberts told Americans that the Constitution doesn’t limit lawmakers’ ability to punish them—by diluting the power of their vote, the bedrock of a democratic society—because they dare to express support for the opposing party. Meanwhile, he will continue to assure wealthy Americans that his court will do everything in its power to safeguard their right to influence elections by buying candidates’ loyalty.

In her powerful Rucho dissent, Kagan pinpointed exactly where Roberts went so awry. She wrote that extreme partisan gerrymanders “undermine the protections” of “democracy embodied in the First Amendment.” She explained how courts can easily determine whether a gerrymander “substantially dilutes the votes of a rival party’s supporters.” She laid out all the tools that courts have already used to invalidate and correct partisan gerrymanders. “That kind of oversight,” Kagan noted, “is not only possible; it’s been done.”

But that didn’t matter to Roberts and his fellow conservatives. They abandoned the Constitution just when its guarantees were most necessary to protect democracy. And they ignored the courts’ proven ability to apply these guarantees in a manner that vindicates free expression. With Rucho, Roberts has turned the First Amendment on its head, denying voters a shield against lawmakers who rig elections by retaliating against political speech. “The practices challenged in these cases,” Kagan wrote, “imperil our system of government. Part of the Court’s role in that system is to defend its foundations.” Thanks in part to Rucho, those foundations will continue to crumble.