http://hosted.verticalresponse.com/435149/2f204c4580/1481501001/3260890ec1/...The guarantee of equal protection under the Wisconsin state constitution is substantially equivalent to the guarantee of equal protection under the Fourteenth Amendment to the U.S. Constitution. Therefore, an equal protection challenge will be subject to the rational basis test articulated by the Supreme Court which states that a law will survive such a challenge so long as “there is a rational relationship between disparity of treatment and some legitimate governmental purpose.” Because it appears that Walker exempted specifically the unions that supported his campaign, opponents may have room to contend that the bill’s disparity of treatment is not rationally related to a legitimate governmental purpose. However, courts have traditionally proven quite deferential to legislatures when applying this rational basis test – therefore, bill opponents will have a formidable challenge in attempting to judicially invalidate the bill.
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The article is quite long and has embedded links. I am not a lawyer but I thought that those working on this should read this. This is the last paragraph.
Ashwin Madia ran as a Democrat against Eric Paulsen for Jim Ramstad's US Rep seat in 2008 and got 41% of the vote.
http://en.wikipedia.org/wiki/Ashwin_Madia