A three-year investigation of Wisonsin Gov. Scott Walker and aides closed for good today with no charges against Walker.

Just like that, the lengthy John Doe investigation into Gov. Scott Walker’s aides and associates is over.

Nearly three years after the probe was launched, retired Appeals Court Judge Neal Nettesheim signed an order shutting down the secret investigation.

In all, Milwaukee County prosecutors brought charges against six individuals as a result of the probe, which was opened in May 2010. Of those, three were former aides to Walker while he was Milwaukee County executive, one was an appointee and another a major campaign contributor.

No additional charges will be filed.

Nettesheim said in an interview Friday that prosecutors reviewed thousands of documents and took testimony from hundreds of witnesses. In addition, Milwaukee County officials raided the homes of several former Walker aides and seized documents from others.

The judge said the investigation had been all but dormant in recent months. The case had been kept open as a way to release documents tied to the criminal charges that already had been filed.

The state Democratic Party’s communications director was noticeably disappointed, taking to Twitter to compare the governor to the infamous cannibal serial killer, Jeffrey Dahmer, for some reason:

https://twitter.com/gjzielinski/statuses/307527092168433664

https://twitter.com/gjzielinski/statuses/307529620037713920

https://twitter.com/gjzielinski/statuses/307533106817146882

Zielinski is known as a “combative” operative in Wisconsin political circles, who throws reporters out of events and has a flawless Pants-on-Fire record with Politifact. His Twitter bio notes he’s a former Washington Post, Chicago Tribune, and Onion writer. A Journal-Sentinel report says he worked for them, too. Surprise.

So far, both Milwaukee Mayor Tom Barrett, Walker’s recall opponent, and the Democratic state party chairman have had to distance themselves from Zielinski.

“The mayor said, ‘Way over the top and very inappropriate,'” said Patrick Curley, chief of staff to Barrett…

Democratic Party Chairman Mike Tate apologized for his aide’s remarks.

“Graeme’s tweet is inappropriate, over zealous and insensitive,” Tate said via email. “He should have chosen a different comparison point in pointing out Gov. Walker has had to spend hundreds of thousands of dollars to avoid criminal charges. He and I regret his comment.”