Question: Which Wisconsin state governor oversaw a vote to significantly limit public employee collective bargaining?

<P0-S0> Recall elections for four Wisconsin state senators were held during the spring of 2012. <P0-S1>  Voters put four state senators up for recall, all Republicans, because of the budget repair bill proposed by Governor Scott Walker and circumstances surrounding it. <P0-S2>  Democrats targeted Republicans for voting to significantly limit public employee collective bargaining. <P0-S3>  Scholars could cite only four times in American history when more than one state legislator has been recalled at roughly the same time over the same issue. <P0-S4>  The recall elections occurred on June 5, with May 8 being the date of the primary election. <SEP> <P1-S0> Scott Kevin Walker (born November 2, 1967) is an American politician who is the 45th and current Governor of Wisconsin. <P1-S1>  First elected governor in the 2010 Wisconsin general election, he won a 2012 recall election and was reelected governor in the 2014 Wisconsin gubernatorial election. <P1-S2>  He also served in the Wisconsin State Assembly and as the Milwaukee County Executive. <SEP> <P2-S0> Recall elections for nine Wisconsin state senators were held during the summer of 2011; one was held on July 19, and six on August 9, with two more held on August 16. <P2-S1>  Voters attempted to put 16 state senators up for recall, eight Democrats and eight Republicans, because of the budget bill proposed by Governor Scott Walker and circumstances surrounding it. <P2-S2>  Republicans targeted Democrats for leaving the state for three weeks to prevent the bill from receiving a vote, while Democrats targeted Republicans for voting to significantly limit public employee collective bargaining. <P2-S3>  Scholars could cite only three times in American history when more than one state legislator has been recalled at roughly the same time over the same issue. <SEP> <P3-S0> In February 2011, a series of public employee protests began in the United States against proposed legislation which would weaken the power of labor unions. <P3-S1>  By March, eighteen states had proposed legislation which would remove some collective bargaining powers from unions, along with another five states which proposed legislation which would negatively affect unions. <P3-S2>  The protests occurred when public employee unions mounted protests against legislation proposed by Republican governors such as Scott Walker (Wisconsin), Rick Scott (Florida), Mitch Daniels (Indiana), Sean Parnell (Alaska), Rick Snyder (Michigan), John Kasich (Ohio), Paul LePage (Maine) and Jan Brewer (Arizona) which, among other things, would strip public employees of some collective bargaining rights as well as require higher employee contributions to pension and health care plans. <P3-S3>  The governors stated they needed these changes in order to cut state spending and balance the states' budgets. <P3-S4>  The protests began in Wisconsin, then spread to Indiana and Ohio, with unions around the country rallying to show their opposition to the proposed legislation. <P3-S5>  Several other states considered similar legislation. <P3-S6>  Virginia, North Carolina, and Texas prohibit formal