An investigative report by KING-TV in February 2017 found that many of the non-federal employees that were likely exposed routinely to nuclear and chemical wastes at Harford were being denied compensation.

However, such claims could still be denied by showing evidence of other external factors that could cause that illness, such as lifestyle choices or prior exposure at other jobs.

Former and current employees at the site with presumed illnesses were eligible to apply for compensation, as long as these existed before the law was enacted in June 2018.

[7] Prior to oral arguments, Washington amended its law with SB 5890 that expanded the presumption to all workers, not just federal contractors, that worked at a radiological hazardous waste facility within the state.

The new law came into effect in March 2022, which the state argued in filings made the case moot since it no longer discriminated against the federal government.

In a unanimous decision, the Supreme Court ruled that the Washington law violated the Supremacy Clause of the United States Constitution by discriminating against the federal government.