Profanity on television, police use of GPS without a warrant, and the status of Jerusalem on passports are grist for the new US Supreme Court session opening Monday, but the main event will be President Barack Obama's landmark health care reform.

The nine justices on the highest court in the land already have 50 cases on the table for the new session, which runs until the end of June 2012.

The court has dealt with up to 75 cases in past sessions, so the extra space could be interpreted as leaving extra room to tackle the sweeping health care reform that Obama championed and signed into law in early 2010.

Ilya Shapiro, an expert on the court at the libertarian Cato Institute, in Washington, described health care as "the so-called elephant in the room," overshadowing all other cases.

"This is definitely the issue of this term," said Michael Carvin, a leading constitutional lawyer for the Jones Day firm in the US capital and who has argued cases in the court.

"It could be the term of the century, or at least of the decade," he said.

The health care legislation extended coverage to an extra 32 million people and fulfilled decades of Democratic dreams of social reform, but was fiercely contested by Republicans. The divisive policy has resurfaced as a key issue in the early stages of the campaign ahead of next year's election.

On Wednesday Obama's administration asked the court to decide whether the law is constitutional, attacking an appeals court ruling in August that struck down a central provision that would requires all Americans to have health insurance by 2014.

The justices, confronted with contradictory lower court rulings, have received three other appeals, including one by a group of 28 US states seeking a complete overhaul of the law.

In all likelihood, the justices will hand down a decision in June. "This will be decided before the (US presidential) election" in November 2012, said Carvin, adding that it will inevitably become a campaign issue.

"Regardless what the decision is, it's going to be one of the most dramatic decisions in the history of constitutional law, because the court will have to decide what the limits are on Congress's power," said Timothy Sandefur, a lawyer at the Pacific Legal Foundation.

The Supreme Court could also take up other hot issues, such as gay marriage and state laws clamping down on immigration.

They are politically very significant because they involve "the power of the states against the power of the national government," said Elizabeth Papez, a constitutional law specialist.

Another equally important case that deals with the separation of powers is one that pits the State Department against the parents of an American born in Jerusalem who wants his passport to read "born in Israel."

The Supreme Court also is expected to weigh in on the definition of "indecency" on television in a case that concerns the appearance of bare bottoms in a TV series and the use of profane language on live shows.

The court will also examine a request from the Obama administration to allow police to track suspects using GPS (global positioning system) satellite technology without a judicial warrant.

The judgment is seen as a key test of the US fourth amendment after a man sentenced for drug dealing on evidence obtained using GPS without a warrant was annulled after it was deemed to have violated his rights.

In both cases, according to Papez, the Supreme Court must reconcile old laws on freedom of expression and the protection of privacy with new technologies.