Affordable Care Act opponents are getting a chance to continue their legal attack on a provision that could require most legal U.S. residents to own health coverage.

U.S. District Court Judge Roger Vinson has decided to let the plaintiffs — officials from 20 states and the National Federation of Independent Business, Nashville, Tenn. — move ahead with parts of a suit that alleges that the Affordable Care Act package violates states’ Constitutional rights.

Vinson has been hearing oral arguments at the U.S. District Court in Pensacola, Fla., on whether he ought to dismiss the case, State of Florida et al. vs. United States Department of Health and Human Services et al., Case 3:10-cv-00091-RV-EMT.

The defendants include the U.S. Department of Health and Human Services (HHS), the U.S. Trescalesasury Department, the U.S. Labor Department, HHS Secretary Kathleen Sebelius, Treasury Secretary Timothy Geithner, and Labor Secretary Hilda Solis.

The Obama administration has argued that the government needed to create the Affordable Care Act, the package that includes the Patient Protection and Affordable Care Act (PPACA), to tackle a situation in which care is more expensive than in the rest of the world, some have no health coverage, and competition among private health insurers is dwindling. They say the government must require individuals to own health insurance or pay a penalty tax to prevent antiselection.

The plaintiffs in the State of Florida suit say the individual health insurance ownership mandate is unconstitutional, and that the government is commandeering state resources to force a

massive expansion of the Medicaid program.

“There is a widely recognized need to improve our healthcare system,” the judge says in an opinion explaining his decision. “How to accomplish that is quite controversial. For many people, including many members of Congress, it is one of the most pressing national problems of the day and justifies extraordinary measures to deal with it.”

Using “extraconstitutional government” to improve the system would be worse, the judge says.

“In this order, I have not attempted to determine whether the line between Constitutional and extraconstitutional government has been crossed,” the judge says. “That will be decided on the basis of the parties’ expected motions for summary judgment, when I will have the benefit of additional argument and all evidence in the record that may bear on the outstanding issues.”

But, from the perspective of the plaintiffs, the plaintiffs have stated a “plausible claim that the line has been crossed,” the judge says.