Labor chairman Ehud Barak prevented his party from fracturing Wednesday when he brokered a deal on Labor's new constitution ahead of what could have been a stormy party convention at Tel Aviv's Dan Panorama Hotel. There had been speculation that Barak's insistence on passing the constitution without making any changes would trigger lawmakers in his faction to join the four Labor rebel MKs in splitting the party. But the rebels' hopes were quashed when Barak made a last-minute deal with his party's three top politicians, Welfare and Social Services Minister Isaac Herzog, Minority Affairs Minister Avishay Braverman, and rebel MK Ophir Paz-Pines. Barak agreed to their demand to hold the next Labor leadership race in October 2012 - a full year before the next general elections - rather than six months later, as he had wanted. The decision changes the old party bylaws that would have required the primary to be held in April 2010, within 14 months of losing a general election. The constitution's approval was good news for Prime Minister Binyamin Netanyahu, who now can rely on his close ally Barak remaining Labor leader - and therefore the party likely staying in the coalition - for the next two-and-a-half years. In his fiery speech to the packed hall, Barak called for party unity while at the same time slamming the rebels' attacks on him. He referred to the four MKs who boycotted the convention as "the flesh of our flesh," but warned them that he would no longer tolerate anarchy in the party. "I came here to tell you, let's join hands - those who are here and those who aren't," Barak said. "It's not too late. And together we can restore Labor to its proper place at the helm of the country. Let's get together and return to lead the government." Responding to six months of rebel attacks against him, which he called "delusional," Barak defended taking Labor into Netanyahu's government and making changes to the constitution that were intended to stabilize a party that, he noted, had had six leaders in a span of just eight years. "There is nothing more fatal than having the party's leaders attacking one another every day," he said. "One day they call me Chavez and the next day Saddam Hussein. These personal attacks are shallow attempts to delegitimize me - I don't want to say character assassination." Rebel MK Eitan Cabel released a statement after the convention saying that the compromise Barak had reached did not change the ideological divide in Labor or diminish the likelihood of a split. His ally in the rebels, MK Amir Peretz, said the convention had actually deepened the rift. Barak's associates expressed hope that Paz-Pines would become more loyal due to the compromise he had supported. But Paz-Pines said he still saw himself as part of the rebel group along with Cabel, Peretz, and MK Yuli Tamir. MK Shelly Yacimovich, who the rebels were hoping would give them the fifth vote needed to split the party, attended the convention and accused Barak of stripping Labor of ideology and making it as undemocratic as Foreign Minister Avigdor Lieberman's Israel Beiteinu Party. "I don't want this party that is so dear to me to become an empty vessel," Yacimovich said to Barak in her speech at the event. "It's nice that you made a deal, but why were such negotiations necessary? Why was such an undemocratic constitution presented in the first place?" Herzog and Braverman declared victory after the convention. They said that in the deal, which was brokered by Histadrut Labor Federation chief Ofer Eini, they had succeeded in keeping the party united by reaching a compromise with Barak, but that preventing a split was now in his hands. "We made [Barak] surrender," Herzog told reporters. "If Barak had kept pushing without compromising, the party would have imploded. We did our part to avoid a historic tragedy, and now it's up to him." Herzog said the most important part of the deal was that Barak had agreed on procedures for holding a primary even if the general election were moved up. He said that had this not been set, Barak would have been able to cancel the leadership race and perhaps even the primary that selects the party's MKs - charges denied by Barak's associates. Earlier Wednesday, Civil Service Commissioner Shmuel Hollander announced an investigation into Barak spokesman Ronen Moshe's insults of Tamir. Moshe has denied Tamir's allegation that he called her a "trash can" in a private conversation, but Hollander said that Moshe, as a civil servant, had broken the law when he criticized Tamir's competence in radio and television interviews.