EVER since Alberto Nisman, an Argentine prosecutor, accused the country’s president and foreign minister of conspiring with Iran to undermine the investigation of the 1994 bombing of a Jewish centre in Buenos Aires, the country has been in turmoil. Mr Nisman was found dead of a gunshot wound in his bathroom just hours before he was due to present his claims to a congressional panel. His allegations against the president, Cristina Fernández de Kirchner, were sensational enough. After his mysterious death, the side of the political divide Argentines found themselves on depended on which conspiracy theory they believed.

On February 25th the judge in charge of investigating Mr Nisman’s allegations against the president and her associates, Daniel Rafecas, threw the case out. In a strongly worded ruling, he wrote that there was “not even circumstantial evidence” to support the allegation that Ms Fernández or her subordinates had interfered with the investigation of the Jewish-centre bombing, or that they had asked Interpol to cancel its arrest warrants for the Iranians suspected of involvement in the attack. The head of Interpol has publicly stated he received no such request.

Despite the decision in her favour, Ms Fernández sounded characteristically combative in a three hour and 40 minute state-of-the-union speech to Congress, her last as president, which she delivered on March 1st. She noted that documents found in Mr Nisman’s safe praised her role in pursuing justice for the 85 victims of the Jewish-centre bombing. “Which Nisman do I go with?” she asked. “With the one who accused us of a cover-up or the one who addressed me, acknowledging all we had done?”

Ms Fernández’s critics found fault with the decision that exonerated her: they said it seemed hastily done and its tone was fawning. But Mr Rafecas’s record will make it hard to paint him as a stooge of the government. He is the author of a book on the Holocaust and spoke at the reconstructed Jewish centre on the 17th anniversary of the attack; he is respected by Argentine Jews. Although he was appointed by Néstor Kirchner, Ms Fernández’s late husband and predecessor, Mr Rafecas has clashed with her administration over the investigation of the vice-president’s involvement in a currency-printing company. The judge ordered a search of the vice-president’s flat. Government representatives have accused Mr Rafecas of leaking information about the case to the media.

Gerardo Pollicita, the prosecutor now investigating Mr Nisman’s claims, must decide by March 5th whether to appeal against the ruling. Higher courts may take weeks to decide whether the 300-page document detailing the allegations, which is based largely on wiretapped telephone conservations, merits another look. But the judge’s refutation is a blow to Mr Nisman’s main theory, that Ms Fernández and the foreign minister, Héctor Timerman, cooked up a scheme to shield Iranian suspects in the bombing in exchange for a trade deal that would bring Iranian oil.

It is unlikely to ease the political tension. Mr Nisman’s death is as mysterious as ever. Did he kill himself? Was he murdered by intelligence agents? Ms Fernández has suggested that rogue agents had fed him with false information and then killed him to discredit her further. The hundreds of thousands of Argentines who marched on February 18th to commemorate Mr Nisman’s death will not be satisfied with anything less than a conclusive explanation. Ms Fernández faces separate investigations over allegations of money-laundering in connection with a hotel company she owns.

In her speech to Congress, she sought to shift the focus to more popular subjects. Argentina is the only country that has reduced its national debt, she claimed, inaccurately. She described bondholders who forced the country into default as “vultures” and “bloodsuckers”. Until she leaves office after elections in October, she will remain a polarising figure, both at home and abroad.

Editor's note: The deadline for Gerardo Pollicita to appeal against the judge's ruling was corrected.