The US Supreme Court justices heard opening arguments on Monday on President Barack Obama's signature health care reform law and appeared to lean in favor of a landmark review.As the nine justices took their seats in a packed courtroom, hundreds of people gathered outside, some chanting and marching for or against the Affordable Care Act, derided by some as "Obamacare."In Monday's 90-minute hearing, the justices considered arguments on the narrow question of whether they have jurisdiction in the case, or must wait until the law has fully entered into force after 2014 to rule on it.From their exchanges, the justices appeared to lean toward the view that the Anti-Injunction Act, which bars legal action to impose prior restraint on Congress' power to tax, does not apply in this case."It seems to make no sense to separate the punishment from the requirement," Chief Justice John Roberts said, referring to the penalties imposed under the law on Americans who refuse to buy health insurance.The government and the 26 states challenging the health care reform as unconstitutional both say the court has jurisdiction, but the court assigned its own lawyer to make the case that it does not."There is nothing in the statute that should be treated as a tax," said Solicitor General Donald Verrilli, arguing for the government. He said the right way to read the Anti-Injunction Act is that it did not apply to the health care act.Gregory Katsas, arguing for the states, said for the Anti-Injunction Act to come into play the purpose of the lawsuit has to be to stop the taxes.But he said, "The purpose of this lawsuit is to challenge the mandate, not the tax."A ruling is not expected until June, but if the court decides it does not have jurisdiction, any action on the law would be set aside at least until 2015.The law's most controversial provision - the so-called "individual mandate" requiring all Americans to buy insurance from 2014 or pay a fine - is to be taken up on Tuesday.The top US court has set aside six hours for oral arguments in the case, the longest in the past 45 years. Hearings typically last only about an hour.Both supporters and opponents of the Affordable Care Act have been holding demonstrations to make their voices heard."It's health care for everybody. It's very important," said Jasper Johnson, a 26-year-old computer technician who came from San Francisco, and was among the handful of people camping out since Friday for the few seats set aside for the public to watch the start of the proceedings."I'm here not only for myself but for the economy as a whole."But many Republicans oppose the measure, with front-running White House hopeful Mitt Romney calling the law an "unfolding disaster for the American economy."His Republican rival, Rick Santorum, made an appearance outside the court.The ruling could have enormous political ramifications, analysts say, especially if the court strikes down part or all of the reform."If the law is struck down, then the administration's signature achievement is gone," Ilya Shapiro, with the conservative publican policy foundation the Cato Institute, told AFP. The law, enacted in 2010 but which will not come fully into force until 2014, is Obama's greatest accomplishment, realising a long-held dream of generations of Democrats.But Republicans seeking to thwart Obama's bid for a second term in the White House see it as an assault on individual liberties, and have vowed to repeal it if elected in the November presidential elections.

Medical students rally in support of the Patient Protection and
Affordable Care Act outside the US Supreme Court Building in Washington,
DC. (Chip Somodevilla/Getty Images/AFP) The main controversy focuses on a measure that requires all Americans to purchase personal health insurance from 2014 or face fines."If they can force you to buy health insurance, they can force you to buy a car, asparagus, a gym membership," said Kenneth Cuccinelli, attorney general of Virginia, one of the states seeking to overturn the law.Other provisions bar insurance companies from refusing to insure people with pre-existing or chronic conditions, who are often now rejected for coverage or forced to pay exorbitant premiums.The companies must also provide certain kinds of coverage that previously were excluded, such as contraception.Opponents argue Congress exceeded its constitutional authority by approving the law.The US Justice Department has hit back arguing the law is within the authority of Congress to regulate commerce and to tax citizens.Among the nine Supreme Court justices, five were appointed by Republican presidents and four by Democrats.- AFP/de