By Greg Stohr 

The fate of President Barack Obama’s health-care law may hinge on the administration’s ability to enlist an unlikely ally: Justice Antonin Scalia, the pillar of the U.S. Supreme Court’s conservative wing.

Scalia, 75, looms as a pivotal vote in the landmark case, the first time the high court has considered a president’s signature legislative victory during his re-election campaign. The court will hear arguments for three days in late March with a decision possible in June — just months before the election.

“It would be a huge coup for the administration to win Scalia over and certainly in the realm of possibility,” said Theodore Ruger, a constitutional and health-care law professor at the University of Pennsylvania Law School in Philadelphia.

The Obama administration needs the vote of at least one of the five Republican appointees on the nine-member court to uphold the law and its requirement that everyone get insurance. It is appealing to Scalia based on the justice’s own words from a 2005 opinion in an unrelated case affirming the federal government’s power to control locally grown medical marijuana.

“Congress may regulate even noneconomic local activity if that regulation is a necessary part of a more general economic regulation of interstate commerce,” Scalia wrote.

Whether that opinion suggests Scalia may vote to uphold the health-care law is a matter of dispute. The administration will have to overcome the conservative instincts of a justice who opposes abortion and gay rights and wrote the decision conferring constitutional protection for gun ownership.

Marijuana Decision

Like health care, the marijuana dispute tested Congress’s power over interstate commerce. The court decided 6-3 that federal prosecutors could press cases even if the drug never crossed state lines and even when its medical use was legal under state law.

Scalia, in his concurring opinion, said the federal ban would be undermined if prosecutors had to make exceptions. He pointed to the Constitution’s provision that lets Congress go beyond the powers the document explicitly lists. That clause permits additional laws that are “necessary and proper” for carrying out Congress’ enumerated powers.

The 2010 health-care law, the Affordable Care Act, extends coverage to an estimated 32 million people who lack insurance, largely via an expansion of the federal-state Medicaid (USBOMDCA) program for the poor. It requires that people get insurance by 2014 or face a tax penalty.

Deriding the law and its mandates has become a staple of the Republican presidential campaign, with candidates calling measure “Obamacare.” Winning the support of Scalia –appointed by former President Ronald Reagan and an icon among legal conservatives — would help blunt those Republican attacks.

Colleagues’ Support

The Obama legal team also may be encouraged that two Republican-appointed federal appeals court judges, both close to Scalia, have said the law is constitutional. And a third said a challenge to the measure was premature.

Still, for Scalia to back a law widely loathed by Republicans would be an exception to his long pattern of conservative positions. He also was the first justice to issue an opinion backing then-Governor George W. Bush over Democratic Vice President Al Gore in the 2000 presidential election deadlock.

Blunt Spoken

Scalia’s combativeness and blunt language have made him one of the court’s most divisive figures. Scalia once told a colleague her reasoning in an abortion case “cannot be taken seriously.” When the court expanded the rights of prisoners at the U.S. naval base in Guantanamo Bay, Cuba, he said the ruling “will almost certainly cause more Americans to be killed.”

Retired Justice John Paul Stevens, who served for two dozen years with Scalia, said in a September interview that Scalia wouldn’t be ideologically driven on the health care decision. Scalia’s personal view wouldn’t have “the slightest impact on his analysis of the constitutional issue.”

That outlook isn’t shared by Brian Fitzpatrick, a former Scalia clerk, who said the justice’s conservative instincts probably will cause him to side with the states that are opposing the health legislation.

“He’s probably still a pretty solid vote to strike down the individual mandate,” said Fitzpatrick, who teaches constitutional law at Vanderbilt University Law School in Nashville, Tennessee.

Justices in Play

Scalia declined to comment, said Kathy Arberg, the Supreme Court’s spokeswoman. Justices as a matter of course don’t discuss pending cases.

Scalia isn’t the only Republican-appointed justice in play in the case. Chief Justice John Roberts and Justices Anthony Kennedy and Samuel Alito similarly have written or joined in opinions affirming federal powers.

The Obama administration invoked Scalia’s marijuana opinion five times in a court filing last month. It argues that mandating insurance coverage for individuals is an essential component of the law. Millions of healthy consumers are needed to expand the premium base because of new requirements that insurers accept people with preexisting conditions and charge them the same rates as other policyholders, the government said.

Scalia’s analysis in the marijuana case “applies remarkably closely, and even more strongly, to this case,” said David Strauss, a constitutional law professor at the University of Chicago Law School.

Sided With States

Lawyers for the 26 states challenging the law disagree. Scalia’s marijuana opinion was “a very modest use of the necessary-and-proper clause,” merely allowing in-state regulation of a drug already banned across state lines, said David Rivkin, who represented the states at an earlier stage.

With health care, there is a thinner connection between the mandate and the rest of the law, said Rivkin, a Washington lawyer with Baker Hostetler LLP.

Scalia votes in other cases suggest skepticism toward federal power. He has backed decisions limiting Congress’ commerce clause authority in 1995 and 2000.

Scalia last year joined Justice Clarence Thomas in saying the court should have considered the validity of a federal ban on body armor possession by convicted felons. And Scalia wrote the 1997 opinion striking down part of the Brady gun control law, saying it infringed the rights of states.

“He certainly is one of the justices who believes very robustly that the federal government is a government of limited and enumerated powers,” Rivkin said.

Republican Appointees

The Republican-appointed appellate judges who have voted to uphold the health care law include Laurence Silberman, a longtime friend who worked alongside Scalia in the Justice Department under President Gerald Ford. The other, Jeffrey Sutton, once served as “one of the very best law clerks I ever had,” in Scalia’s words.

Both relied heavily on the Supreme Court’s ruling in the marijuana case, known as Gonzales v. Raich, using reasoning that backers of the law say may resonate with Scalia.

“I think he’d come into the argument skeptical about the legislation,” said Doug Kendall, president of the Washington- based Constitutional Accountability Center, which supports the law. “But I think he’ll have a hard time squaring the challenge to it with his opinion in Raich.”