Timothy D. Russell, 49, was charged in January with embezzling more than $20,000 from a veterans' charity Walker hosted when he served as Milwaukee County executive. Assistant District Attorney Bruce Landgraf said Monday the plea deal would be the subject of a hearing Thursday but he did not provide details, the Milwaukee Journal-Sentinel reported.
Parker Mathers, an attorney for Russell, did not immediately respond to a request for comment, the newspaper said.
Russell was deputy chief of staff for Walker and county housing director during Walker's term as county executive. Court documents indicate he transferred funds from the Heritage Guard Preservation Society, into personal accounts and then spent the money on vacation trips.
He is also accused of stealing from campaign finance accounts of candidates for Milwaukee County Board.
He has been linked to -- but has not been charged in -- the establishment of a computer system in the county executive's office that prosecutors allege was used for secret communication between Walker's official county staff and workers in Walker's 2010 campaign for governor.
Kelly Rindfleisch, who formerly worked as deputy chief of staff for Walker, has already pleaded guilty to using the back-channel computer system to raise campaign funds for a former Republican legislator and unsuccessful candidate for lieutenant governor, Brett Davis.
A Milwaukee County jury in October convicted Kevin Kavanaugh, a former Walker appointee to the Veterans Service Commission, of stealing more than $51,000 intended for military veterans. Darlene Wink, a county employee when Walker was county executive, previously agreed to plead guilty to two misdemeanor charges of using public resources to raise funds for a political campaign.
Walker, who retained a defense attorney in February and started a legal defense fund in March, had been on a list of prosecution witnesses for Rindfleisch's trial.