Gov. Chris Gregoire is joining with three other Democratic governors seeking to fight the controversial health-care lawsuit filed by more than a dozen state attorneys-general, including Rob McKenna.

The lawsuit filed in March challenges the constitutionality of the health-care law's requirement that everyone purchase health insurance.

Gregoire and Democratic governors of Michigan, Pennsylvania and Colorado sought permission Wednesday to file a friend-of-the-court brief in support of an Obama administration motion to dismiss the lawsuit.

In those states, like Washington, Republican attorneys-general have joined the lawsuit against the wishes of the Democratic governors.

But it's not clear that Gregoire and her fellow Democratic governors will be allowed to intervene in the controversial lawsuit.

The Florida federal judge presiding over the case recently ruled that no one could file amicus briefs in support or opposition to the federal government's motion to dismiss the lawsuit.

U.S. District Judge Roger Vinson added that he wasn't likely to accept such briefs even at later stages in the lawsuit.

Gregoire and the other governors filed a motion Wednesday arguing they should be granted an exception, because, well, they are governors.

Their motion argues that as governors they are in a "unique position to respond to the plaintiffs' erroneous allegations" that the health-care law is unconstitutional because it deprives states of their sovereignty.

In a news conference at a Seattle cupcake shop whose owner supports the health-care law, Gregoire said the court needs to consider that the Republican attorneys-general do not represent their entire states.

The new law, Gregoire said, will benefit Washington by ending discriminatory insurance practices and help control costs by ensuring everyone pays into the insurance system.

"We can offer the court certain perspectives that are not theoretical, but represent real-world experience," Gregoire said.

The governors' also argue they can provide specific examples showing why the health-care law is constitutional as a matter of interstate commerce.

For example, Harborview Medical Center in Seattle is affected by the load of uninsured when it cares for trauma patients from nearby states.

Attorneys from the Seattle law firm Schroeter, Goldmark & Bender are doing the legal work for the Democratic governors free of charge, along with a Florida attorney who also is working pro bono, according to Gregoire.

McKenna has said his participation in the lawsuit also will cost the state no money. Florida Attorney General Bill McCollum is taking the lead on the lawsuit.

McKenna released a statement Wednesday afternoon saying 20 states have now joined the lawsuit, including 16 attorneys-general and four governors, because "health care reform is too important to build on an unconstitutional foundation."

In addition to the individual insurance requirement, McKenna said the law's "massive expansion" of the Medicaid program "will unconstitutionally require states to spend billions more on this program at a time when state budgets are already in crisis."

A hearing on the government's motion to dismiss the health-care lawsuit is scheduled for Sept. 14.