Art. 158 No. 1 ZGB; divorce presupposes proof of a valid marriage. The court must examine ex officio whether the marriage sought to be dissolved exists in law and may not evade this preliminary question by referring to the absence of divorce grounds (consid. 1). Where the validity of the marriage is disputed, it cannot be determined incidentally in divorce proceedings but only by a declaratory action for recognition of marital validity. For a Swiss party, the absence of recognition by the competent Swiss administrative authorities and of registration in the home commune precludes treating the marriage as proven in the divorce action; foreign-law validity issues are likewise reserved to the validity action.
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