I. In any case in which a divorce might be decreed, the superior court, on petition of either party, may decree a legal separation of the parties, which separation shall have in all respects the effect of a divorce, except that the parties shall not thereby be made free to marry any third person and except as hereinafter provided.
II. A person concerning whom a legal separation has been decreed may file a motion to amend the decree to one of divorce. The court may then consider whether justice requires that such a change be made, and, upon such consideration, the court may, in its discretion, grant such a motion.