a battle with unions. If it was, we would have eliminated collective bargaining entirely or we would have gone after the private-sector unions." As part of the cost savings resulting from the changes to collective bargaining, Walker pointed to significant reductions in the premiums for health insurance for many school districts. Prior to the deficit reduction bill, WEA Trust, which is affiliated with Wisconsin's largest teachers union, dominated the market for health insurance for the state's school districts. The changes to collective bargaining made it easier for school districts to change health insurance providers and negotiate better premiums. Walker claimed that Wisconsin school districts have saved an estimated $30 million as a result of the change. John Doe campaign finance investigation In August 2012, the first investigation, which had been launched by John Chisholm, Milwaukee County District Attorney, a Democrat, into missing funds, was rolled into a second John Doe probe based on a theory that Governor Walker's campaign had illegally coordinated with conservative groups engaged in issue advocacy during the recall elections. The initial John Doe judge, retired Kenosha County Circuit Judge Barbara A. Kluka, overseeing the John Doe investigation issued 30 subpoenas and 5 search warrants. She also issued a secrecy order which meant those being investigated were legally bound from discussing any facet of the investigation publicly. On October 29, 2013, she recused herself from the investigation without explanation. Kluka's replacement, Judge Gregory Peterson, quashed several subpoenas in January 2014, saying "there was no probable cause shown that they violated campaign finance laws". On July 16, 2015, the Wisconsin Supreme Court ruled 4–2 that Walker did not illegally collaborate with conservative groups during the recall campaigns. Writing for the majority in the case, Justice Michael Gableman stated: "To be clear, this conclusion ends the John Doe investigation because the special prosecutor's legal theory is unsupported in either reason or law," he said, "Consequently, the investigation is closed." In March 2017, a federal judge dismissed a lawsuit filed against the investigators of the case. 2011–2013 budget proposal Wisconsin faced an anticipated deficit of approximately $3.6 billion in the 2012–2013 budget cycle which must be balanced according to state law. Walker's proposed budget cut $834 million in state aid for K–12 education, which would be a 7.9% reduction from the prior budget. He proposed a 5.5% decrease in the maximum amount of funding school districts can receive from state