An in-depth investigative report from the Guardian U.S. sheds new light on the relationships between Gov. Scott Walker and donors to the Wisconsin Club for Growth during the governor's 2012 recall election, raising questions about influence over at least one legislative effort that would have benefited one significant donor.

The Guardian U.S. sifted through a set of 1,500 leaked documents from the John Doe probe into Walker's campaign and conservative groups that supported him during the recall effort, including Wisconsin Club for Growth. Some of the documents have been seen before, while others were published for the first time on Wednesday.

The documents show multiple instances of Walker soliciting contributions from wealthy donors not for his campaign, but for Wisconsin Club for Growth.

The report raises questions about legislative efforts to shield lead paint manufacturers from lawsuits seeking compensation for lead poisoning. The leaked documents show $750,000 in donations to Wisconsin Club for Growth from Harold Simmons, the owner of one of the United States' leading producers of lead used in paint until it was banned. 

"In the same time frame" the donations occurred. Walked signed into law changes passed by the Republican-led Legislature that would have made companies like NL Industries effectively immune from compensation claims for lead paint poisoning. 

According to one document cited in the report, a lobbyist for NL Industries suggested to Senate Majority Leader Scott Fitzgerald, R-Juneau, which language should be used to make the effective immunity retroactive. The phrase suggested by the lobbyist is the one that was added to an amendment, which was passed and signed into law but later blocked by a federal court. 

A spokeswoman for Fitzgerald did not immediately return a request for comment.

Federal courts have since overturned most of the changes outlined in the Wisconsin law.

"But the point remains: had the new provisions been allowed to stand, they had the potential to save the company and others like it millions of dollars in damages," the report reads.

The Guardian U.S. report notes there is no evidence Republican legislators tried to change those laws as a direct result of Simmons' donations to the group that supported some of them in their recall elections. But it closes with questions about the appearance of quid pro quo resulting from that relationship.

Walker's campaign pushed back on the report.

"As widely reported two years ago, the prosecutor’s attorney stated that Governor Walker was not a target. Several courts shut down the baseless investigation on multiple occasions, and there is absolutely no evidence of any wrongdoing," campaign spokesman Joe Fadness said.

Documents previously released from the Doe investigation showed that mining company Gogebic Taconite had donated $700,000 to Wisconsin Club for Growth before the Legislature passed a bill softening environmental regulations on iron mining throughout the state.

In a 4-2 ruling last summer, the state Supreme Court ordered an end to the John Doe investigation. Prosecutors have since asked the U.S. Supreme Court to overturn that ruling, arguing some of the justices who ruled in favor of shutting down the probe should have recused themselves since they had received donations from the groups being investigated. 

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