Huron Consulting, a company earning its bread and butter by helping other public companies file clean financial statements, is now restating its own financials back to 2006.

The company filed a Form 8-K with the Securities and Exchange Commission advising investors to look for new financial statements for 2006, 2007, 2008, and the first quarter of 2009. The company also replaced its chairman and CEO, Gary Holdren, with two new top officers who will split the job—George Massaro as chairman and James Roth as CEO.

Huron said the restatement will correct accounting related to four specific business acquisitions where payments received by sellers were “subsequently redistributed among themselves and to other select Huron employees.” The firm said the estimated impact on net income and EBITDA (earnings before interest, taxes, depreciation, and amortization) for all restated periods is $57 million.

Huron said the purchase agreements for the four acquisitions now under scrutiny involved earn-outs, or payments made over time contingent upon achieving certain performance targets. In its restatement announcement, the company said its Audit Committee recently learned that “the selling shareholders had an agreement among themselves to reallocate a portion of the earn-out payments to an employee of the company who was not a selling shareholder.” Huron said the sellers have recently amended their agreements related to these payments and anticipates that the non-cash compensation charges causing the restatement will not continue past July 31.

Huron didn’t identify the employee who received payments, nor did it provide any cause for Holdren’s departure. Lynn Turner, managing director in forensic accounting at LECG, said Huron’s published statement suggests “there were some sort of kickback payments being made, which raises serious business and ethical questions.”

While every public company dreads the black eye that comes with a restatement, the blow to Huron could be harder than usual, said Turner. “Its product rests on the credibility and reliability of its people, and this action appears to call that into question,” Turner said.

Steve Quinlivan, an attorney with Leonard, Street and Deinard who focuses on mergers and acquisitions, said it’s not entirely clear whether there was an intention to deceive with respect to the earn-out agreements that just came to the audit committee’s attention. “It would seem a bit drastic to me if they did this behind Huron’s back and Huron did not know,” he said. “It is not one of the risks normally considered when you draft earn-out arrangements.”

Neither Huron nor its audit firm, PricewaterhouseCoopers, had any further comment on the restatement announcement.