By Cynthia Johnston CAIRO, March 22 (Reuters) - A prominent Egyptian judge predicted on Thursday that fraud would mar next week's national referendum on changes to the country's constitution and said he expected a dismal turnout. The judge, Mahmoud Mekky, became a symbol of the judiciary's struggle for independence from Egypt's executive branch after he was sent to a disciplinary council for making public allegations of abuse in 2005 national elections. President Hosni Mubarak's government, which called Monday's plebiscite, says the amendments are reforms, but opponents say their aim is to strengthen his ruling party's grasp on power. "I expect fraud ... and I especially expect that the number of people who will go to the polls to cast votes will be very small," Mekky said. "Turnout in the upcoming referendum will not exceed, under any circumstances, 5 percent." The government said the turnout in a similar referendum in May 2005 was about 54 percent. Observers and the opposition said it was closer to 10 percent. The amendments include an anti-terrorism clause that enshrines sweeping police powers of surveillance and arrest. They would also allow the president to dissolve parliament unilaterally and weaken judicial oversight over elections, which have been marred by complaints of widespread irregularities. "They prevent the judicial authority from monitoring the executive authority in terms of citizens' rights and freedoms," Mekky said. The government says all elections are fair. Opposition groups, including the powerful Muslim Brotherhood, plan to boycott the ballot. The Brotherhood is likely to be hardest hit by the changes, which would bar political activity based on religion and could thus quash its longstanding hope of gaining recognition as a legal political party. "I call for international monitoring, and for monitoring by human rights groups and civil society," Mekky said. He added that he and several other judges had formed a voluntary committee to monitor any complaints of abuse during the vote. Egypt's state news agency has reported the Supreme Judicial Council, which supervises the judiciary, has authorised the deployment of judges to oversee the vote. But Mekky said only several hundred would take part and their participation in election committees was only symbolic. "There will be no real judicial supervision," he said. International rights watchdog Amnesty International has called the constitutional amendments "the greatest erosion of human rights" in Egypt since emergency laws were put in place in 1981 after the assassination of President Anwar Sadat. A judicial disciplinary panel ultimately cleared Mekky last year of any wrongdoing for speaking out on the 2005 polls, while another judge had a promotion withheld and was warned he could be dismissed for any future offences.