Thus ends one of the most abusive political witch hunts in decades. The Supreme Court shot down an attempt by Wisconsin prosecutors to revive its John Doe investigation into Governor Scott Walker and his aides, a years-long investigation marked by intimidation of witnesses and abuse of power by the Milwaukee County district attorney’s office. It upheld a previous state Supreme Court ruling ending the probe, and implicitly blessed a new law that prevents prosecutors from abusing their offices in the future:

The U.S. Supreme Court on Monday let stand Wisconsin’s top court’s decision to halt a special prosecutor’s investigation into possible unlawful coordination between Republican Governor Scott Walker’s campaign and conservative advocacy groups.

The justices declined a prosecution appeal of the Wisconsin Supreme Court’s July 2015 decision to end the probe into whether conservative groups and Walker’s campaign to survive a recall vote in 2012 had violated campaign finance laws. …

A federal judge in May 2014 initially stopped the probe after the Wisconsin Club for Growth filed a lawsuit accusing investigators of sidelining the group from political activities and violating its rights to under the U.S. Constitution to free speech, association and equal protection under the law.

A federal appeals court later said the investigation could continue. But in a parallel case in state court, Wisconsin’s high court ultimately stopped it.

In October 2015, Walker signed a new state law that prohibits prosecutors from using the Wisconsin’s secret investigation statute, a measure that had been used to convict four of his aides and investigate his campaign, to probe political crimes.

The Journal-Sentinel questions the timing:

The order comes soon after documents were leaked that show the extent to which the Republican governor and his aides worked closely with a supposedly independent group on recall elections. The documents include details about large donations from those who benefitted from laws approved by Walker and GOP lawmakers.

It’s worth recalling how the Wisconsin Supreme Court characterized the investigation and the claims of criminal activity. It castigated the prosectors for their “paramilitary-style home invasion,” accused them of fomenting a state of tyranny, and wrote that citizens of Wisconsin are fortunate that the prosecutors picked on people who could afford to fight back. The prosecution, the court stated, was “unsupported by reason or law”:

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 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). …

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.

Despite the Journal-Sentinel’s spin, the court specifically found the targets of the investigation “wholly innocent of wrongdoing.” Nor were the targets the only people who found their rights trampled by politically motivated prosecutors using arcane and unsupported legal theories about campaign-finance law. A later court action forced prosecutors to send 159 notices of secret surveillance this past January, conducted illegally by an improperly appointed “special prosecutor.” That was on top of the home invasions, property seizures, and explicit intimidation conducted on lawful citizens that characterized the entire John Doe probe.

The Supreme Court has rightfully slammed the door on the masterminds of these tactics, more reminiscent of 20th-century dictatorships than of American self-government. These prosecutors will be lucky if they can continue to practice law — but they shouldn’t.