Rome, December 28 - Italy's Constitutional Court has been asked to decide the future of the troubled ILVA plant in southern Italy, raising questions about the jurisdiction of the courts and prosecutors versus state authority over environmental issues. Prosecutors in the southern city of Taranto confirmed late Thursday that they've appealed to one of Italy's highest courts to overturn the Italian government's "save ILVA" decree, in a case that has pitted the government, workers, and unions against the courts, residents living around the plant, and green politicians. When the national government of Premier Mario Monti passed the decree just weeks ago, it was aimed at allowing the steel plant, which for years has been emitting pollution, to continue production while it makes upgrades. But prosecutors, who have been trying since July 26 to shut down the plant, employing about 20,000, say the government has overstepped its bounds. According to prosecutors, the government is interfering with their ongoing investigation of an environmental disaster at the second-largest steel plant in Europe. Friday, the president of the Green Party Angelo Bonelli praised the appeal, saying the courts have "a duty to protect the health of citizens, workers". The "save ILVA" decree was passed by the government cabinet on November 30 after the company had warned it risked "imminent" closure due to the criminal probe into an environmental scandal that saw several of its top managers arrested. ILVA supporters have warned that if the Taranto plant closes, it could trigger the closing of a larger one in Genoa, which cumulatively could cause an 8 billion euro loss to the Italian economy, according to figures released by the government last fall.