Washington (CNN)It is D-Day once again for Obamacare, the President’s hard-won health law, which stands again before the Supreme Court.
Opponents are asking the Supreme Court to determine a critical question: does the text of the law authorize tax subsidies for 6.4 million Americans who have already received help to afford health coverage?
As the justices work toward a self-imposed June deadline, they will seek to answer that question, knowing that if they side with the challengers the ruling could severely destabilize the structure of the entire law. Here are five questions to understand what is going on: