CAIRO  - Brawls broke out in an Egyptian courtroom as judges tried to debate rulings on Tuesday that could either bolster the country’s new Islamist President Mohamed Mursi, or undermine him in his power struggle with the military.Mursi’s allies in the Muslim Brotherhood hailed a “decisive” day in the country’s democratic transition and hundreds of supporters came to protest at the courthouse, accusing the generals of using the judiciary to undermine his authority.Despite his election victory in June, Mursi has yet to form a cabinet and there is no fully functioning government, parliament or constitution for Egypt, deepening the sense of turmoil that has pushed the economy to the brink of a balance of payments and budget crisis.Legal opinion is split on whether the Cairo administrative court will strike down Egypt’s constituent assembly, formed by an Islamist-dominated parliament with the tasked of re-writing Egypt’s constitution.The divisions were reflected at the court, where members of the public pushed and elbowed lawyers and one other, angrily shouting demands and counter demands. “Down, down with military rule,” cried supporters of the Brotherhood who want the constituent assembly to continue its work.That drew an angry response from their opponents. “Down, down with the rule of the (Brotherhood’s) Supreme Guide,” shouted a woman as the courtroom descended into mayhem.“Cancel the session,” said lawyer Nabiel Gabriel. “This isn’t justice... I am holding Mursi personally accountable for this chaos. He has a responsibility to establish order.”Judge Abdel Salam el-Naggar told the crowd the court would not be intimidated and suspended proceedings to allow the atmosphere to cool before reconvening lawyers in a separate court chamber.“This court has always taken pride that its chambers are open to the public,” he told them. “We were shielded by this public. But what happened in that chamber - is such terrorism appropriate?” As the turmoil continued, people banged on the courtroom door, threatening to break in.The power struggle unleashed by the overthrow of Hosni Mubarak last year has shifted from the streets to the ballot box and now the courts as Islamists vie for influence with their perennial adversaries in an army-led establishment. At Tuesday’s hearings judges will decide if an assembly drafting a new constitution should be scrapped. They will also hear appeals against decrees by the military and one from Mursi that recalled an Islamist-dominated parliament that the generals had dissolved.“Everybody should know that the conspiracy against parliament will end in failure, as well the conspiracy against the constituent assembly and the constitution, and the president himself,” said Essam al-Erian, leader of the Brotherhood’s Freedom and Justice Party, in al-Ahram newspaper.Brotherhood supporters warned the army not to undermine the country’s new elected institutions.“Who elected the constitutional assembly? Parliament. And who elected parliament? The people. We are the ones to determine our fate,” said 20-year-old student Ahmed Mohamed el-Sayed, a member of the Brotherhood’s Freedom and Justice Party (FJP). On its Facebook page, the FJP declared the Cairo administrative court’s deliberations “decisive” for the nation.  The military took power from Mubarak promising a new era of accountable, civilian rule but the transition has been chaotic and inconclusive.It oversaw the first open leadership contest in Egypt’s history, only to claw back vital powers from the new president, leaving Egyptians still wondering who really controls the Arab world’s most populous nation since Mursi took office on June 30.Self-proclaimed guardians of the Egyptian people, the generals have taken greater control over how the constitution is formed, angering the Brotherhood but comforting some liberals who fear Islamists are intent on dominating the state to impose their conservative agenda.A previous constituent assembly was dissolved by court order, after liberals and others quit the body complaining it was so dominated by Islamists that it failed to reflect Egypt’s diversity.Some legal experts said the military was right to dissolve parliament because it was acting on a ruling by the country’s Supreme Constitutional Court that had challenged the rules under which the legislature was elected.“We are debating judicial, constitutional verdicts that are not debatable,” said Sameh Ashour, head of Egypt’s lawyers’ syndicate, in newspaper al-Shorouk.So far, Mursi has avoided a major confrontation with the military council led by Field Marshal Hussein Tantawi - figurehead of the turbulent transition.At a military graduation ceremony on Tuesday, Mursi sat alongside Tantawi and other senior officers and made a speech in which he paid homage to the leaders of the armed forces during the uprising against Mubarak.