HARRISBURG, Pa.—A federal judge in Pennsylvania said the insurance-buying mandate in the 2010 health care reform law is unconstitutional, the latest ruling over an issue likely to be taken up by the U.S. Supreme Court.

U.S. District Judge Christopher Conner in Harrisburg, Pa., said the Commerce Clause of the U.S. Constitution did not give Congress power to require nearly all Americans to buy health insurance, whether they want it or not. The requirement is scheduled to take effect in 2014.

"The nation undoubtedly faces a health care crisis," Judge Conner wrote on Tuesday. "Scores of individuals are uninsured and the costs to all citizens are measurable and significant.

"The federal government, however, is one of limited enumerated powers, and Congress' efforts to remedy the ailing health care and health insurance markets must fit squarely within the boundaries of those powers," he added.

President Barack Obama pushed for the law to help stem soaring health care costs and provide coverage to more than 30 million uninsured Americans.

Many Republicans have pledged to undo the law, and at least two dozen lawsuits have challenged it.

Three federal appeals courts have reviewed the Patient Protection and Affordable Care Act.

One in Atlanta voted down the individual mandate, one in Cincinnati upheld it, and one in Richmond, Va., let it stand by rejecting challenges on jurisdictional grounds.

The Supreme Court often takes cases to resolve disputes among federal courts. Its 2011-2012 term begins next month.

Tracy Schmaler, a U.S. Justice Department spokeswoman, said after Tuesday's ruling: "We believe, as other federal appeals courts have held, that the law is constitutional."

The Pennsylvania case had been brought by a York County couple, Barbara Goudy-Bachman, 48, and Gregory Bachman, 56.

They said they dropped their health insurance coverage in 2001 because their premiums exceeded their mortgage payments, they had only limited use for such insurance, and they preferred to pay for medical costs on their own.

If appealed, Judge Conner's ruling would be reviewed by the federal appeals court in Philadelphia.

Judge Conner was appointed to the bench in 2002 by President George W. Bush.

The case is Goudy-Bachman et al. vs. Sebelius et al., U.S. District Court, Middle District of Pennsylvania, No. 10-00763.