The letter to Mr. Victor said the AFL-CIO had concluded that "WCRI, like the insurance companies it depends upon for its financial support, operates to promote the interests of the workers' compensation insurance industry."

WCRI states on its Web site that it provides "high-quality, objective information about public policy issues involving workers' compensation systems" and "does not take positions on the issues it researches; rather, it provides information obtained through studies and data collection efforts, which conform to recognized scientific methods. Objectivity is further ensured through rigorous, unbiased peer review procedures."

But according to the labor group's letter, "WCRI's Board of Directors and its Research Committee are almost entirely officers of the major insurance companies that sell workers' compensation insurance."

WCRI, which does ongoing studies of the functioning of workers' comp in the various states, the AFL-CIO said, is dependent for its research "on insurance industry data, which cannot be publicly disclosed, even to the public officials to whom WCRI presents its reports."

In its entire history, the AFL-CIO wrote, WCRI has not "produced a single study on the effect and practices of the insurance industry in pricing and administering the workers' compensation system."

According to the letter, AFL-CIO participated in WCRI peer review process and found that it "not only flawed, but also fails to meet even the most rudimentary standards of scholarly research."

According to Mr. McGarrah, the WCRI has focused on outmoded managed care systems and ignored cost efficient self-insured workers' comp programs that guarantee high quality medical care that are run by John Hopkins University and the Marriott group.

Despite major concerns by business and labor over the price of worker's comp insurance, WCRI has looked at injury treatment, but not examined alleged fixing and manipulation of prices, Mr. McGarrah charged. "This is a clear issue," he said.