A judge Friday ruled against a bid by a former aide to Gov. Scott Walker to have his felony embezzlement charges thrown out based on an ethical transgression by a defense attorney.

That means former Walker aide Timothy D. Russell will stand trial starting Dec. 3, unless a last-minute plea deal comes through. Russell worked as deputy chief of staff and housing director while Walker was Milwaukee County executive.

It was also disclosed Friday that a plea bargain had been offered to Russell but that he hadn’t accepted it. He’s charged with two felony embezzlement counts accusing him of stealing more than $20,000 from a veterans group and taking more that $2,500 from a county supervisor candidate whose campaign Russell was helping. He’s also charged with a misdemeanor for embezzling a smaller sum from another candidate.

Defense lawyer Parker Mathers said he was still holding out hope he might discover evidence that would clear Russell in a batch of emails he hasn’t fully reviewed.

Mathers and Milwaukee County Assistant District Attorney Bruce Landgraf declined to say what evidence Russell hoped to find in the emails, which were provided to him by prosecutors on a compact disc. Russell’s home and work computers were seized by prosecutors last year as part of a secret John Doe investigation.

At an earlier hearing, Landgraf said Russell was claiming that money he’s accused of stealing from the Heritage Guard Preservation Society was actually payment for work he did for the nonprofit.

The Heritage Guard group was taken over by Russell at Walker’s direction to serve as a financial arm to handle donations collected for Operation Freedom, Walker’s annual veterans fair at the zoo while he was Milwaukee County executive.

Landgraf has subpoenaed Russell’s tax records, which would be provided at his trial.

Landgraf also has included Walker on a lengthy witness list for Russell’s trial and would subpoena the governor to testify on the authenticity of an Oct. 20, 2009, document in which Walker transferred control of Operation Freedom to Russell as president of the Heritage Guard group.

If Russell stipulates the document is authentic, the governor’s testimony wouldn’t be needed at trial, Landgraf said.

In court Friday, Russell argued that the prosecution against him was tainted by one of his former lawyers in the case, Dennis Krueger.

Krueger got in hot water in August for failing to disclose that he had taken a job as an assistant prosecutor in Fond du Lac County while still working as Russell’s defense lawyer. Circuit Court Judge David Hansher described that action an ethical violation of attorney rules.

Russell argued Friday that Krueger’s dual role as defense attorney and prosecutor meant that his embezzlement charges should be dismissed, even though Krueger’s prosecutor job had barely begun at the time and he wasn’t doing any work for the Milwaukee County district attorney.

Hansher disagreed, saying there was no basis to dismiss the case.

“There was an ethical violation but not a legal violation,” the judge said.

Landgraf said the plea deal that had been offered to Russell was revoked because he didn’t accept it by the end of Friday’s hearing. However, if Mathers finds some strong evidence from the emails to show Russell didn’t commit the offenses, he’d reconsider, Landgraf said.

Russell is one of six former aides and associates of Walker who were charged as part of an investigation that’s lasted more than two years. Included in that group is Kevin Kavanaugh, a Walker appointee to the county Veterans Service Board, who was convicted in October of stealing more than $51,000 in money donated to help veterans and their families. Kelly Rindfleisch pleaded guilty last month to felony misconduct for doing campaign work while working in Walker’s county executive office. Darlene Wink, Walker’s county constituent services director, pleaded guilty in February to two misdemeanor counts for doing campaign fundraising from the courthouse.