His campaign slogan is "Shake-Up Springfield" but a federal judge used another descriptor of how Bruce Rauner and his former company GTCR conducted themselves in a failed business deal -- "Hard Ball."
Court documents obtained by NBC 5 and the Chicago Sun-Times shed new light on the business philosophy of the Republican candidate for governor and how he might run the state if he is elected.
The deal was sealed after Kirk traveled to Chicago from her home in Arizona and met with Rauner at his GTCR office in what was then the Sears Tower.
At the time Kirk was a partner at the accounting firm of Arthur Andersen.
Together they started LeapSource, a business-outsourcing firm to provide financial and accounting services to other companies.
The relationship started strong but soon there were problems. In a lawsuit she later filed against GTCR, Kirk said she received only a part of the $65 million start-up money she said was promised by GTCR, which is disputed by Rauner. Rauner and GTCR claimed Kirk was spending money fast and furiously with little to show for it, which is disputed by Kirk.
By the fall of 2000 the Rauner-Kirk business relationship was unraveling.
"The only thing Chris did on a consistent basis, on a timely basis was spend," Rauner said in a sworn deposition adding, "the hard thing is cutting expenses, the hard thing is laying people off. But that's what good companies do when times are tough."
Rauner, who sat on the board of LeapSource, helped engineer the firing of Kirk in February 2001.
According to the lawsuit, Rauner told another board member if Kirk sued over her firing, "I will bury her ... I will bankrupt her with legal fees. I don't know if she has a family or not but if she does she better think twice about this."
In her sworn deposition Kirk alleged she was also warned by a colleague saying, "Bruce had threatened" her and would make her "radioactive."
That colleague was Thomas Gilman, another plaintiff along with Kirk in the lawsuit, who sat on the Board of LeapSource and is a former CEO of DaimlerChrysler Financial Services Americas.
Gilman said Kirk was concerned about the behavior of GTCR and the threatening things that were said to her.
"Were you involved in any conversation where threatening things were said to Ms. Kirk?" Gilman was asked in his deposition. His answer was "yes."
The Rauner campaign responding to questions posed by NBC 5 and the Chicago Sun-Times strenuously denied ever threatening Kirk, her family or her livelihood.
Federal District Judge Robert Broomfield later dismissed almost all of the counts of Kirk's lawsuit saying there was no breach of fiduciary responsibility by GTCR, but the judge's ruling did not address the alleged threats.
Judge Broomfield wrote Rauner's GTCR: "chose to 'play hard ball,' adding "undoubtedly it would have been preferable to plaintiffs if defendants (GTCR) had comported themselves with an [a]spirational ideal of good corporate governance practices ... that go beyond the minimal legal requirements of corporate law."
At a recent campaign stop, while not speaking to this case, Rauner touted his business record but acknowledged, "We're not perfect. Not every company we invested in worked out. But our track record is stellar," he said.
Both Christine Kirk and Thomas Gilman declined to comment on this story. No one from GTCR returned a call for comment.