Three years ago the U.S. Supreme Court handed down McConnell v. FEC, a decision that upheld McCain-Feingold’s restrictions on political speech. The future seemed bleak for any limits on government regulation of speech and association.

But things are looking up. Today the Supreme Court handed down its decision in Federal Election Commission v. Wisconsin Right to Life.

McCain-Feingold made it a federal crime for any corporation to broadcast, 30 to 60 days before an election, any communication that mentions a federal candidate for elected office and is aimed relevant voters. Wisconsin Right to Life (WRTL) is an ideological corporation that accepted funding from other corporations. Its members wanted to run ads in 2004 urging citizens of their state to contact its two senators and urge them to oppose a filibuster of judicial nominees. Sen. Russ Feingold, one of the senators and a co-author of the law in question, was running for re-election. Wisconsin Right to Life’s advertising plans thus constituted a federal crime. At least, they were a crime if the relevant part of McCain-Feingold was constitutional as applied to WRTL. In fact, McCain-Feingold was constitutionally invalid in this case and probably many others.

To understand why requires a quick summary of campaign finance law. Congress long ago prohibited contributions to candidates from the general treasuries of corporations and labor unions. But corporations could fund ads commenting on the issues of the day. However, if those ads directly advocated the election or defeat of a candidate, they became an attempt to circumvent the ban on corporate contributions and thus a federal crime. In Buckley v. Valeo, the Court said such “express advocacy” contained words like “elect” and “defeat.” If an ad did not use the words, it was not express advocacy and hence, not subject to campaign finance regulation.

In the 1990s some businesses and labor unions started funding advertising that met the legal standards for issue advocacy. The ads were legal and often highly critical of vulnerable members of Congress in the run up to an election. McCain-Feingold made such speech illegal. It said corporations could not fund ads that mentioned a candidate for federal office with 30 to 60 days of an election. The McConnell Court went along arguing that the ads in question were the “functional equivalent of express advocacy.” In the WRTL decision, the author of the majority opinion, Justice Roberts, has contracted rather than expanded the scope of government regulation. He has done so by redefining the meaning of express advocacy: “a court should find that an ad is the functional equivalent of express advocacy only if the ad is susceptible of no reasonable interpretation other than as an appeal to vote for or against a specific candidate.” The WRTL ad seemed to a reasonable person to be attempt at grassroots organizing. Hence, WRTL wins.

But this standard implicates more than this case. Many of the ads in the 1990s that were the target of McCain-Feingold might have been free of regulation under this standard. Reasonable people could have believed that the ads were attempts to persuade voters to contact their representatives. The political space free of government regulation seems to have expanded. Indeed, it seems possible that many fewer ads will be judged the “functional equivalent of express advocacy” in the future.

So, the good guys won one at last. “Enough is enough,” as Justice Roberts writes in considering efforts to further expand government control of politics.

But still there is reason to worry. The majority did not declare the relevant part of McCain-Feingold unconstitutional. Justice Alito did suggest a willingness to hear constitutional challenges to the McConnell decision (and hence, to McCain-Feingold). Justice Roberts also set out some criteria for the “express advocacy” that are fairly broad. An ad that mentions “an election, candidacy, political party, or challenger; or [that takes] a position on a candidate’s character, qualifications, or fitness for office” could become express advocacy depending on future judgments by the Court and perhaps, by the Federal Election Commission.

An important battle has been won. The war continues.