The latest opposition to the bill was voiced by the AFL-CIO and a group of asbestos trust funds whose assets would be shifted to the trust fund created by the legislation. A law firm representing several of the trust funds said that if the bill is enacted, the existing trust funds would argue in court that moving existing trust funds into the new system was unconstitutional.

That would be a tremendous blow to the system, because under the proposed law, the money in the existing trust funds would provide some of the seed money the new system would use to pay claims in its earliest years.

The proposed law would establish new criteria for settlements?as well as reduce lawyers' payments from settlements to 5 percent, 10 percent for appeals. That provision is designed as a major sweetener for conservatives in Congress who are anti-trial lawyer. The White House shares similar sentiments.

The latest darts are being thrown against the background of a hearing on the bill set for tomorrow before the Senate Judiciary Committee. The committee also plans to vote on the bill Thursday.

In its letter of opposition, the AFL-CIO said the legislation "fails to ensure victims just and timely compensation and would leave tens of thousands of individuals with no remedy at all."

The letter explains that the bill would prevent 60,000 to 80,000 individuals with varying degrees of illness from access to any forum for as long as two years in the event that the trust fund is not operation.

"The bill also includes provisions establishing medical criteria for lawsuits for individuals who have both asbestos-related disease and silica-related disease that will bar many of them from seeking redress in the courts for their silica-related injury, while at the same time limiting their compensation from the asbestos fund to $25, 000," the letter said.

At the same time, the Des Plaines, Ill.-based Property Casualty Insurers Association of America (PCI) declared its "strong opposition" to the bill, S. 852.

"Federal legislation must provide an effective, efficient and exclusive remedy for all asbestos claims, pending and future," said Carl Parks, senior vice president, federal government affairs for PCI.

He added that, "S. 852 does not meet these goals. Moreover, the legislation has the potential to permanently damage insurance markets and the U.S. economy."

The letter voicing opposition from existing trust funds was signed by Theodore B. Olson, a lawyer at Gibson, Dunn & Crutcher in Washington, D.C.

Mr. Olson said in the letter his clients believe the law is an unconstitutional taking of assets because the bill would require the surrender of substantially all the assets of these judicially-created asbestos trusts to a national fund.

"This national fund would then be used to pay some claimants to whom the trusts have no obligation, but would be unavailable to pay some claimants to whom the trusts do have obligations," the letter added.