The long unraveling of the so-called “John Doe II investigation” convened by partisan district attorneys in Wisconsin is now complete. This case was about using vague campaign-finance rules to intimidate conservative groups and smear Republican officials, including Gov. Scott Walker. No charges were filed in the John Doe II investigation and it was halted by both the state and federal courts.

Today, the Wisconsin Supreme Court releases its final disposition in the case:

To be clear, this conclusion ends the John Doe investigation because the special prosecutor’s legal theory is unsupported in either reason or law. Consequently, the investigation is closed. Consistent with our decision and the order entered by Reserve Judge Peterson, we order that the special prosecutor and the district attorneys involved in this investigation must cease all activities related to the investigation, return all property seized in the investigation from any individual or organization, and permanently destroy all copies of information and other materials obtained through the investigation. All Unnamed Movants are relieved of any duty to cooperate further with the investigation.

The theory of the prosecutor’s case was that conservative groups had illegally coordinated with candidates for office by means of issue advocacy. Applying well-settled principles of election law, the Wisconsin high court holds that this goes too far because “[d]iscussion of issues cannot be suppressed simply because the issues may also be pertinent in an election.” The courts have long treated express advocacy—that is, speech directly supporting a candidate for election—as wholly separate from issue advocacy—that is, speech about political issues. The court explains that, insofar as the Wisconsin statute purports to regulate issue advocacy the way that it does express advocacy, it is overbroad and vague under both the First Amendment to the U.S. Constitution and Wisconsin’s own Article 1, Section 3.

The court did not spare the feelings of the special prosecutor. As my pal @Popehat noted, “unsupported in reason” is a particularly harsh thing to say. The court did not stop there:

The special prosecutor has disregarded the vital principle that in our nation and our state political speech is a fundamental right and is afforded the highest level of protection. The special prosecutor’s theories, rather than “assur[ing] [the] unfettered interchange of ideas for the bringing about of political and social changes desired by the people,” Roth, 354 U.S. at 484, instead would assure that such political speech will be investigated with paramilitary-style home invasions conducted in the pre-dawn hours and then prosecuted and punished. In short, the special prosecutor completely ignores the command that, when seeking to regulate issue advocacy groups, such regulation must be done with “narrow specificity.” Barland II, 751 F.3d at 811 (quotations omitted).

The Court’s conclusion lauds the targeted individuals and groups for fighting back against the investigation:

Our lengthy discussion of these three cases can be distilled into a few simple, but important, points. It is utterly clear that the special prosecutor has employed theories of law that do not exist in order to investigate citizens who were wholly innocent of any wrongdoing. In other words, the special prosecutor was the instigator of a “perfect storm” of wrongs that was visited upon the innocent Unnamed Movants and those who dared to associate with them. It is fortunate, indeed, for every other citizen of this great State who is interested in the protection of fundamental liberties that the special prosecutor chose as his targets innocent citizens who had both the will and the means to fight the unlimited resources of an unjust prosecution. Further, these brave individuals played a crucial role in presenting this court with an opportunity to re-endorse its commitment to upholding the fundamental right of each and every citizen to engage in lawful political activity and to do so free from the fear of the tyrannical retribution of arbitrary or capricious governmental prosecution. Let one point be clear: our conclusion today ends this unconstitutional John Doe investigation.

This is extraordinarily firm language about the disposition of these cases. Moreover, the Wisconsin court’s use of the state’s constitution to invalidate the investigation forecloses additional appeal to the federal courts for the partisan district attorneys, despite what they may be claiming. The Wisconsin Supreme Court gets the last say on what the state’s constitution requires. They did so here, making federal intervention moot.

This decision does not punish the instigators of the John Doe II investigation, beyond tanking their reputations for pursuing what a concurring justice calls “a fishing expedition into the lives, work, and thoughts of countless citizens.” A federal civil rights lawsuit was shut down by the 7th Circuit last year on the grounds that it was premature to involve the federal courts before the state courts had a chance to resolve the claims. That lawsuit, or one like it, may be revived. A state action for civil damages is also a possibility.