The "John Doe" probe into Scott Walker's time as Milwaukee County Executive is over. But the debate over how the investigation will affect Governor Walker's political future is still alive.

Shortly after the retired judge overseeing the John Doe probe announced today that the investigation is over with no additional charges, State Democratic Party chairman Mike Tate held a conference call with reporters. Tate noted that over the last three years, the investigation led to criminal convictions against six close associates of Governor Walker, and many more of the governor's colleagues were given legal immunity in return for their testimony. Tate says there's evidence that Walker knew about some of the questionable activity, and Tate wants the governor to release e-mails and other documents that may be connected to the case.

"I think it's important that we understand the full nature and behavior of what transpired here. Because this has been something that has been such a prominent part of Scott Walker's time as governor, as well as the fact that numerous people have gone to jail over this."

But Milwaukee County prosecutors may not release more documents. Even if more material does come out, a former Democratic state lawmaker isn't sure the governor will be harmed prior to the 2014 election. UW-Milwaukee governmental affairs professor Mordecai Lee says Walker showed good political skills over the last 15 months and used private money to hire excellent criminal defense lawyers. "I suspect that when he runs for re-election, next November, this will be old history: that he survived a difficult time with his Boy Scout image still intact."

Lee says he expects the Democrats' campaign against Walker next year is more likely to focus on whether the governor has met his 2010 campaign promises for job growth in Wisconsin.