EDGERTON, Wis. — Wisconsin Gov. Scott Walker insisted Thursday that there was nothing illegal about corporate leaders’ donations to a conservative group that helped him and Republican legislators fend off efforts to recall them from office.

Walker responded to questions about a Guardian report on the donations during a news conference in an Edgerton parking lot to highlight his transportation budget. The newspaper obtained more than 1,000 pages of leaked documents from a secret investigation into whether Walker’s campaign illegally coordinated with Wisconsin Club for Growth and other outside groups as he was fighting a bid to oust him from office over his signature law stripping most public employee unions of nearly all of their bargaining rights.

The state Supreme Court halted the investigation in 2015, ruling the coordination was legal since it didn’t lead to express advocacy, a political buzzword for ads that specifically call for a candidate’s defeat or election. The U.S. Supreme Court is set to consider whether to review that ruling later this month and the Guardian report has thrust the matter back into the headlines. The documents detail Walker and his fundraisers’ efforts to persuade business executives around the country to give to the Club for Growth, which ran the ads.

Sounding irritated at times, Walker said no one has faced more scrutiny than he has during his six years as governor. Walker said Thursday that the courts have repeatedly found the investigation was baseless.

“This is old news,” the governor said. “You want to argue about something that’s already been discussed in the courts? Because people didn’t win in the courts under the law, they want to have a discussion where they’re giving out bits and pieces of information, trying to change the court of public opinion.”

Walker didn’t acknowledge working with the Club for Growth or even mention its name. Asked why he wouldn’t acknowledge having worked closely with it, he said only that he and his supporters were “under attack” in early 2011 after the union restrictions had passed and they thought it was important to get the message out about how the restrictions would help the state.

“We thought it was appropriate to get the message out about the facts, not talking about advocating for or against, expressly advocating for or against candidates, but getting the message out that the reforms would work and indeed they have and that’s what we focused in on,” Walker said.

The Guardian’s documents show that Harold Simmons was among the corporate executives who donated to the Club for Growth. Simmons was the owner of NL Industries, which was a major producer of lead that was used in paint before the practice was banned due to health risks. The documents show Simmons gave the club a total of $750,000 in 2011 and 2012 at the height of the recalls.

Walker and the Republican-led Legislature passed a law in 2013 retroactively shielding lead paint makers from liability, raising questions of whether the measure was payback for the donations. Walker said during the news conference that nobody should be surprised the GOP passed the law that he’d been pushing for “litigation reform” for years before becoming governor.

“Nobody should be shocked,” Walker said. “I did what I said I was going to do. If I did something different than what I said I would do, then voters would have a right to question.”

Whoever leaked the documents to the Guardian committed a crime, since John Doe investigations are akin to grand jury investigations, in which information is kept secret. Walker told Milwaukee radio station WTMJ-AM earlier Thursday that he would support an investigation into who leaked the documents.

“I think those involved in law enforcement in this state, if they want people to take seriously the orders of the court, should certain do that no matter what the issue is. Otherwise what kind of a system do we live in?”

Assembly Speaker Robin Vos, a Rochester Republican, and two other GOP state representatives sent a letter to Attorney General Brad Schimel on Thursday asking for the appointment of a special prosecutor to investigate the leak. Schimel, a Republican, tweeted he was considering his options. His spokesman, Johnny Koremenos, declined to comment, saying Schimel wouldn’t discuss details that could jeopardize a potential or ongoing investigation.


Associated Press reporter Gretchen Ehlke in Milwaukee contributed to this report.