On the other hand, Ginsburg said, "The people who don't participate in this market are making it more expensive for those who do."
"You could say that about buying a car," Scalia retorted, noting that if enough people don't buy cars the cost could go up.
But, unlike cars, almost everyone eventually will be required to use the health care system, Verrilli said in defense of the law. Without health insurance, he said, "you're going to the market without the ability to pay for what you're going to get."
Demonstrators returned Tuesday to the sidewalk outside the Supreme Court, with more than 100 supporters of the law circling and chanting, "A healthy America is a productive America," ''Protect the law," and, "I love Obamacare."
More than a dozen opponents held a news conference criticizing the bill.
Supporters, two of them wearing statue of liberty costumes, marched to the song "Walking on Sunshine" and Stevie Wonder's "Signed, Sealed, Delivered I'm Yours," being played over a loudspeaker. A trumpet player played "When the Saints Go Marching In" and "this little light of mine," and supporters changed the lyrics to ones supporting the health care law.
One demonstrator opposing the law wore a striped prison costume and held a sign, "Obama Care is Putting the US Tax Payer in Debtors Prison."
Rep. Michele Bachmann of Minnesota, a former Republican presidential candidate, joined a tea party press conference of opponents of the law. Calling the law "the greatest expansion of federal power in the history of the country," she said, "We are calling on the court today: Declare this law unconstitutional."
Associated Press writer Jessica Gresko contributed to this report.
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