A Sidney man serving 50 years in prison for child rape has won an appeal before the state’s high court that will toss his conviction and get him a new trial. Attorney’s for Eric L. Bard, now 28, argued in December that he deserved a new trial because a judge discussed the case with the prosecutor without the defense counsel present. On Thursday, the Maine Supreme Judicial Court agreed with that argument. “We are persuaded that Bard was deprived of the fair process to which he was entitled,” said the opinion published Thursday on the court’s website. Gina Yamartino, his attorney, said Bard, who is being held at the Maine Correctional Center in Windham, knows about the decision, and that she plans to meet with him Friday.