A federal court in Chicago ruled that the investigation of Wisconsin Governor Scott Walker's office and two dozen conservative groups can continue.

The court lifted an injunction by a federal judge who ruled that the Democratic prosecutor did "not show probable cause that the moving parties committed any violations of the campaign finance laws.”

The abuse of power and prosecutorial misconduct in this case is incredible. The so-called "John Doe" investigation is secret. Not even the targets of the investigation can speak out about it. Here's a sampling of what the conservative groups in Wisconsin had to go through:

The anti-Walker probe included raiding the homes of targeted activists, seizing their private correspondence, phones and computers — including the computers, phones and emails of their spouses and other family members. Under the Doe’s draconian gag orders, conservatives subjected to such raids were threatened with imprisonment if they spoke about it. And because the probe was secret, the prosecutors could not be held accountable for their conduct.

In May, a federal judge finally put his foot down and ordered the probe stopped. But the appeal to the liberal 7th district court in Chicago was successful:

Walker has been dogged by secret investigations, first of aides and associates before he became governor and now on his recall campaign and other conservative groups.

Wisconsin Club for Growth and its director, Eric O'Keefe, filed a federal civil rights lawsuit in February to halt the latest investigation, which began in secret in 2012. They argued it was a violation of their First Amendment rights and an attempt to criminalize political speech.

No one has been charged in the latest probe and prosecutors have said Walker is not a target.

A federal judge in May sided with the group and issued a temporary injunction blocking the investigation. The appeals court overturned that ruling, calling it an abuse of discretion.

The case largely centers on the type of political activity being done by the conservative groups during the recall campaign and whether that work required them to follow state laws that bar coordination with candidates, requires disclosure of political donations and places limits on what can be collected.

Under Wisconsin law, third-party political groups are allowed to work together on campaign activity and engage in issue advocacy, but they are barred from coordinating that work with actual candidates.

Prosecutors have said in court filings that Walker and his top aides illegally raised money and coordinated campaign advertising and other activity with Wisconsin Club for Growth, the state Chamber of Commerce and more than two dozen other conservative groups during the 2011 and 2012 recalls.

So the attempt to criminalize political speech will continue. Meanwhile, Democrats and their union allies use the exact same tactics and nobody bothers them.

In their report on the original ruling of the judge in May, the Wall Street Journal showed the true purpose of the secret probe:

Democrats would love to intimidate and muzzle the local activists who rallied to Mr. Walker's recall defense. And the subpoenas all but shut down these activists, forcing them to hire lawyers and defend themselves rather than contribute to the political debate in an election year. Beyond 2014, the prosecutors' goal seems to be raise the cost of participation so the subpoena targets decide to quit politics.

If you think the tactics sound a lot like those used in the IRS targeting scandal, you are correct.