Attorney-General Menahem Mazuz on Monday defended how the police handled the investigation into former MK Azmi Bishara on suspicion of treason. In a lengthy response to a letter from Likud MK Michael Eitan asking why Bishara had not been arrested, Mazuz's assistant, attorney Shai Nitzan, defended police procedures, citing shortcomings in legislation about parliamentary immunity. The police and the Shin Bet (Israel Security Agency) are investigating allegations that Bishara spied for Hizbullah during the Second Lebanon War, providing targets and classified military information. Some of the suspicions against Bishara were revealed to the public last month when the former Balad chairman refused to return to Israel from a trip overseas. Police permitted Bishara to leave the country even though he had been questioned twice under warning by the police's International Serious Crimes Unit. Bishara resigned his Knesset seat from overseas. When he resigned he lost the parliamentary immunity that had prevented his arrest. Nitzan wrote that had investigators turned to the Knesset with a request to remove Bishara's immunity before the investigation was revealed to the public, it might have harmed the investigation. Even after the investigation reached the stage at which detectives decided to make it's existence public, Nitzan wrote, "the law enforcement systems did not believe that they had legal justification to prevent his departure overseas."