Those following the so-called John Doe investigation in Wisconsin know that a federal judge issued a preliminary injunction shutting down the secret investigation that local prosecutors were conducting into almost all of the conservative advocacy organizations in Wisconsin. Their crime? Supposedly coordinating their efforts on public-policy issues with elected officials such as Republican governor Scott Walker and with each other.

In a civil-rights lawsuit filed by Wisconsin Club for Growth, one of the targets of the investigation, federal district court judge Rudoph Randa put an end to this partisan witch-hunt, saying that the prosecutors were trying to criminalize political speech. That decision has been appealed to the Seventh Circuit Court of Appeals by the prosecutors, who are particularly upset over the fact that the judge refused to give them immunity from civil liability after he concluded they had acted without probable cause and because their interpretation of the law was “simply wrong.”

On Tuesday, four former commissioners of the Federal Election Commission, including Lee Ann Elliott, David Mason, Darryl Wold, and me, filed an amicus brief in the appeals court on the side of the conservative organizations unfairly targeted for exercising their First Amendment rights. Our brief is available here. Former FEC chairman Brad Smith also filed an amicus brief in the case.

Based on our extensive experience in interpreting the Federal Election Campaign Act, implementing regulations, devising enforcement policy, and investigating violations of campaign-finance laws, we argue that issue advocacy is at the core of the rights to free speech, to assemble, and to petition the government for a redress of grievances.

We also point out that the public’s right to engage in issue advocacy, including coordinated activity, is as protected at the state level as it is at the federal level. Wisconsin is failing to draw the sharp line that the FEC and the courts have drawn between regulating express advocacy for candidates and issue advocacy.

What local prosecutors did in Wisconsin is a classic example of the kind of behavior our brief says the Supreme Court has frowned on as chilling core political speech: “Neither the Supreme Court nor this Court [the Seventh Circuit] has ever endorsed such invasive, open-ended investigations of issue advocacy.” In fact, not a single decision by the U.S. Supreme Court or the Seventh Circuit upholds the type of punishment of coordinated issue advocacy that Wisconsin prosecutors were pursing.

Oral arguments in the case are next Tuesday. Hopefully, the Seventh Circuit will uphold Judge Randa’s decision stopping this Star Chamber investigation. And with any luck, the civil-rights lawsuit filed against these prosecutors will not only result in a large judgment that deters this type of investigation from ever happening again, but will spur the state legislature to repeal laws that are clearly and obviously unconstitutional.

 - Hans von Spakovsky is a senior legal fellow at the Heritage Foundation.