Sudden Supreme Court vacancy seizes US campaign spotlight

The future of the US Supreme Court grabbed center stage in the country's presidential campaign with the sudden death of Justice Antonin Scalia, setting up an election-year battle over who should succeed him on a nine-member bench that interprets US law over such hot-button issues as abortion, gay marriage, healthcare and immigration.

The death of the 79-year-old conservative justice, announced by Chief Justice John Roberts, promises to provoke a major confrontation between President Barack Obama, a Democrat, and the Republican-controlled Senate over who will replace Scalia later this year.

The prospect of such a battle drew swift and furious comment from candidates vying to be elected president in November.

The US president has the job of nominating justices, and the Senate has the job of confirming. Senate Majority Leader Mitch McConnell, whose Republicans control the Senate, issued a statement saying the vacancy should not be filled until Obama's successor takes office next January so that voters can have a say in the selection.

In California for a summit of leaders from Southeast Asia, Obama pledged to tap a replacement for Scalia and said he was confident the Senate would have "plenty of time" to review and vote on the nomination.

"I plan to fulfill my Constitutional responsibilities to nominate a successor in due time," said Obama, who has the opportunity to become the first president to appoint three justices since Republican Ronald Reagan, who appointed Scalia in 1986. Obama did not indicate who he would nominate.

Another Obama nominee has the potential to swing the court in a more liberal direction, making this particular slot the most contentious in modern politics. The last time a Senate of one party confirmed the choice of the opposite party during an election year was in 1988, when Justice Anthony Kennedy, another Reagan appointee, was elevated to the high court.

Democratic presidential candidate Hillary Clinton urged Obama to nominate Scalia's replacement despite McConnell's threat.

"The Republicans in the Senate and on the campaign trail who are calling for Justice Scalia's seat to remain vacant dishonor our Constitution," Clinton said in a statement. "The Senate has a constitutional responsibility here that it cannot abdicate for partisan political reasons."

Republican presidential candidates Ben Carson, a retired neurosurgeon, and Ted Cruz, a US senator from Texas, earlier had called on the president to leave the seat vacant until the next administration.

"Justice Scalia was an American hero," Cruz, a former Supreme Court law clerk, wrote on Twitter. "We owe it to him, & the Nation, for the Senate to ensure that the next President names his replacement."

Senator Charles Grassley of Iowa, who chairs the Senate committee that would vet a court nominee, also called on the White House to wait for the next president.

Both political parties already had made the future of the country's highest court a campaign issue even though it usually fails to resonate with voters and rarely ranks as a top issue in public opinion polls.

Debating the court allows both Democrats and Republicans to argue policy planks that are central to their message.

Democratic presidential hopeful Hillary Clinton often speaks at campaign rallies about the recent decisions of the court, such as legalising gay marriage, and how a Republican president might name justices who could undo that decision.

Her Democratic rival, Bernie Sanders, often rails against the 2010 Citizens United decision, which legalized unlimited campaign spending by individuals and corporations.

Democrats would likely be pleased to see Obama name a replacement, which would tip the balance of the nine-member court in favor of liberals after several years favoring conservatives by a 5-4 majority.

Despite the court's conservative credentials, Republicans have been highly critical, telling voters that a Republican president is needed to name jurists who will overturn such decisions as Roe vs Wade in 1973 legalizing abortion and one in 2015 legalizing same-sex marriage along with two decisions upholding aspects of Obama's 2010 signature healthcare law.

"The next president must nominate a justice who will continue Justice Scalia's unwavering belief in the founding principles that we hold dear," US Senator Marco Rubio of Florida said in a statement.