The United States Supreme Court embarks today on three days of momentous hearings into President Barack Obama's healthcare reforms that could not only upend the 2012 election campaign but also redraw the limits of Congressional power and the division of authority between federal government and the states.
The oral arguments before the nine justices come two years after the then Democrat-controlled Congress passed Obama's greatest legislative achievement, without a single Republican vote. Now, after a string of conflicting rulings in lower courts, the country's highest judicial authority will rule whether "Obamacare" is constitutional - or whether all or part of it should be struck from the statute books.
Despite unprecedented pressure, the court has refused to lift its ban on live television or radio coverage. Since Saturday, queues have been building for the 200 public seats in the colonnaded courtroom where the black-robed justices will question lawyers for the Government and the 26 states opposed to the law.
A host of demonstrations will take place outside the court building across the street from the US Capitol.
The hearings will last six hours in all, the longest for any case in almost half a century. Public opinion is split roughly evenly on the law, the biggest overhaul of healthcare in the US since the 1965 Medicare and Medicaid acts that set up government schemes for the elderly and the poor. For the first time it would bring close to universal coverage to a country where a sixth of the population now lacks health insurance.
It would do so by retaining America's system centred on employer-based coverage and operated by for-profit insurance companies. But the latter will henceforth have to provide coverage for all who apply - and in return everyone, healthy or otherwise, left uncovered will be required to buy coverage or face a fine. This so-called "individual mandate" is at the heart of the controversy.
The arguments will be spread over four sessions. This morning was to be devoted to what may be termed the "cop-out" option - that because key provisions, including the mandate, do not kick in until 2014 and 2015, the court cannot rule now upon the Act's legality. If the justices agree, they would avoid pronouncing on a major political issue in the midst of the presidential campaign.
The crunch issue comes tomorrow: whether the individual mandate is an unconstitutional expansion of central power. The Obama Administration says it is essential if reform is to work, but opponents charge that Congress has overstepped its authority. On Thursday, the argument shifts to what happens if the individual mandate is struck down - in other words, must the law then be overturned in its entirety? In the afternoon, the justices will take up the argument of 26 Republican-controlled states objecting to Obamacare's expansion of Medicaid as a violation of states' rights.
The court will not hand down its ruling until late June. Many analysts suspect Obamacare may, in fact, survive. Not since the New Deal has the Supreme Court rejected a central piece of socio-economic legislation enacted by Congress, they point out. Nor will a court anxious to restore its image as impartial arbiter want to be siding so obviously with the Republican White House candidates, all of whom have vowed to repeal Obamacare if elected.