A unanimous U.S. Supreme Court on Tuesday struck down a law Washington state enacted in 2018 that presumed compensability for certain conditions suffered by federal employees and federal contractors at the Hanford nuclear reservation.

The Hanford worker presumption singled out the federal government for unfavorable treatment, the high court said in U.S. v. Washington.

“The law thereby explicitly treats federal workers differently than state or private workers,” the court said. “And, in doing so, the law imposes upon the federal government costs that state or private entities do not bear. The law consequently violates the supremacy clause unless Congress has consented to such regulation through waiver.”

Gov. Jay Inslee in 2018 enacted H.B. 1723, creating a presumption that respiratory disease, beryllium disease, and neurological and heart conditions experienced within 72 hours of exposure to fumes or chemicals are compensable injuries for the nearly 10,000 federal contractor employees at the decommissioned nuclear production facility. The presumption also covers various forms of cancer suffered by workers at the Hanford facility where the U.S. Department of Energy is overseeing the cleanup from the production of weapons-grade plutonium for the nation’s nuclear arsenal during World War II and the Cold War.

A federal district court dismissed a lawsuit by the federal government after ruling that the presumption fell under a federal waiver of immunity. The 9th Circuit Court of Appeals in August 2020 agreed that the presumption was within the scope of the waiver and didn’t violate the doctrine of intergovernmental immunity.

The Department of Justice, in asking the high court to review the decisions, argued that the 9th Circuit decision was “profoundly wrong.”

At the outset, the nation’s top court said it was not persuaded by Washington’s argument that the dispute was moot as a result of legislation enacted earlier this year.

The state argued that Mr. Inslee's signing of S.B. 5890 in March to expand the scope of the presumption for Hanford workers eliminated the need for the nation’s top court to intervene.

That bill repealed statutory language through which the Hanford presumption applied only to federal workers.

The new law “mooted the basis” for the federal government’s complaint, the state argued.

The Supreme Court, however, said a case is not moot unless it is impossible for it to grant any effectual relief, and that money is at stake.

“The United States asserts that, if we rule in its favor, it will either recoup or avoid paying between $17 million and $37 million in workers compensation claims that lower courts have awarded under the earlier law,” the court said.

WorkCompCentral is a sister publication of Business Insurance. More stories here.