Wisconsin Democrat Mary Burke attacked her Republican opponent Gov. Scott Walker on Monday for having a poor record on campaign ethics -- but Burke hired a political adviser who has prior convictions for using taxpayer resources for political campaigning.

"I'm just disappointed our governor set such a low bar for campaign ethics," Burke said Monday morning, according to WBAY-TV in Green Bay. "As governor I'm going to make sure I bring back the trust and honesty that we deserve for the highest office."

But Burke's attack has been complicated by the fact that her own senior political adviser, Tanya Bjork, was herself convicted in a major campaign ethics scandal.

In 2009, when Bjork was appointed to a state job by Walker's predecessor Gov. Jim Doyle, the Milwaukee Journal Sentinel reported:

Tanya Bjork, 38, was convicted of two misdemeanors in 2005 for her role in the largest political scandal in state history. Bjork served as a chief of staff to former Sen. Brian Burke (D-Milwaukee), who was convicted of a felony and misdemeanor in 2005 as part of a widespread investigation that uncovered political campaigning using taxpayer resources. Before she worked for Burke, she worked for the Assembly Democratic Caucus.

Bjork pleaded no contest to charges that she altered records and illegally solicited campaign funds in the Capitol.

Good-government groups met the appointment with skepticism.

In addition to Doyle, Bjork worked for President Obama's 2008 and 2012 campaigns in Wisconsin.

Bjork's presence on Burke's campaign will make it harder for her to capitalize off of the release of thousands of emails related to an investigation into illegal use of public resources for campaigning that led to the convictions of six former Walker staffers. The secret "John Doe" probe closed last year without any charges against Walker himself.

In an emailed statement, Burke spokesman Joe Zepecki wrote: "This is nothing more than a desperate attempt by Scott Walker and his allies to distract from the chorus of voices calling for an explanation as to why Walker's past public statements are at odds with the content of the John Doe emails released last week."