President Obama’s Latina nominee for the US Supreme Court yesterday suffered the embarrassment of seeing her decision in a race case overturned by the same institution that she hopes to join.

The court split 5-4 along ideological lines as it ruled in favour of white firefighters claiming racial discrimination against the City of New Haven, Connecticut, which had discarded the results of promotion exams because black candidates had scored poorly.

Judge Sonia Sotomayor, whose Senate confirmation hearings on her nomination are to begin in two weeks’ time, had previously rejected the claim in a perfunctory verdict in the appeals court. Conservative critics have said that her ruling symbolises her penchant for “identity politics”.

As the first Hispanic woman to be nominated for the Supreme Court, Ms Sotomayor has come under intense scrutiny on such issues. Rightwingers have accused her of being a “reverse racist”, highlighting remarks in which she suggested a “wise Latina woman with the richness of her experiences would more often than not reach a better conclusion than a white male”.

Newt Gingrich, the former Speaker of the House of Representatives, has asked what would have happened if a Supreme Court nominee had said: “My experience as a white man makes me better than a Latina woman.” He added: “New racism is no better than old racism.”

Mitch McConnell, the leader of Senate Republicans, said that he would ask for more time to review hundreds of boxes of material from Ms Sotomayor’s time working with the Puerto Rican Legal Defence Fund. Patrick Leahy, the chairman of the Senate Judiciary Committee, who will oversee confirmation hearings next month, is expected to push for an early vote and yesterday sought to play down the significance of the Supreme Court’s ruling. “Judge Sotomayor and the lower court panel did what judges are supposed to do: they followed precedent.”

The White House press secretary, Robert Gibbs, said that Ms Sotomayor’s position on the case had “little political significance . . . except to render a fairly definitive opinion that she follows judicial precedent and that she doesn’t legislate from the bench”.

Justice Anthony Kennedy, who often tips the balance on the Supreme Court, sided with conservatives as he ruled against New Haven’s actions. “Whatever the city’s ultimate aim, however well intentioned or benevolent it might have seemed, the city made its employment decision because of race. The city rejected the test results solely because the higher-scoring candidates were white.”

The case centred on a firefighters lieutenants’ exam in 2003. After no African-Americans scored high enough to warrant a promotion, the city’s civil service board rejected the results and decided against any immediate promotions.

When 18 white firefighters — including an Hispanic — claimed racial discrimination, New Haven insisted that it was simply trying to avoid being sued by black firefighters, who argued that the test was biased against them.

Times Recommends

• No apology for Germany’s own Nazi victims
• Intricate web of fear and hope tying down deal
• Victims remembered a year after Mumbai attacks