A court case against a translator who leaked US government secrets was conducted in secret because it centred on the revelation that the FBI had eavesdropped on Israeli embassy phone calls, it was revealed yesterday. The extraordinary limitations in place for the prosecution of Shamai Leibowitz, who was sentenced to 20 months in prison for disseminating classified information, meant that even the judge sentencing him did not know what he was supposed to have leaked. All I know is that it's a serious case," Judge Alexander Williams said last year. "I don't know what was divulged other than some documents, and how it compromised things, I have no idea." But now Richard Silverstein, the blogger to whom Leibowitz passed his information, has come forward to defend his source. Leibowitz passed him about 200 pages of verbatim records of phone calls and conversations between embassy officials, saying that he believed the documents revealed Israeli officials trying unlawfully to influence US policy and edging towards military action against Iran. There has been dismay among civil liberties and open government advocates who point to pledges made by Mr Obama before his election to seek new transparency in Washington. Instead, his administration has launched a record number of prosecutions under the Espionage Act - five including the Leibowitz case. Previously, there had been only four such prosecutions opened by all previous administrations.