Sharp questioning by the Supreme Court's conservative justices has cast serious doubt on the survival of the individual insurance requirement at the heart of President Barack Obama's historic health care overhaul.
Arguments at the high court Tuesday focused on whether the insurance requirement "is a step beyond what our cases allow," in the words of Justice Anthony Kennedy.
He and Chief Justice John Roberts are emerging as the seemingly pivotal votes.
Justices Antonin Scalia and Samuel Alito appeared likely to join with Justice Clarence Thomas to vote to strike down the key provision. The four Democratic appointees seemed ready to vote to uphold it.
The conservatives questioned whether the government can force Americans to carry health insurance, wondering in arguments over President Barack Obama's health care overhaul if Congress might next force people to buy broccoli or burial insurance.
"If the government can do that, what else can it" do? asked Scalia, referring to the individual mandate portion of the Patient Protection and Affordable Care Act.
The congressional requirement to buy health care insurance is the linchpin of the law's aim to get medical insurance to an additional 30 million people, at a reasonable cost to private insurers and state governments. Virtually every American will be affected by the court's decision on the law's constitutionality, due this summer in the heat of the presidential and congressional election campaigns.
Recognizing the significance of the case, the justices are allowing audio of the arguments to be released on the same day. The audio of Monday's arguments can be found here.
Scalia, as well as Roberts, Alito and Kennedy, pressed Solicitor General Donald Verrilli on whether people can be forced to buy things like cars, broccoli and burial insurance if the government can make them buy health insurance.
Kennedy at one point said that allowing the government mandate would "change the relationship" between the government and its citizens.