In the event that any clause, sentence, paragraph, chapter, or other part of any title, is adjudged by any court of competent or final jurisdiction to be invalid, such judgment does not affect, impair, nor invalidate any other clause, sentence, paragraph, chapter, section, or part of such title, but is confined in its operation to the clause, sentence, paragraph, section, or part thereof directly involved in the controversy in which such judgment has been rendered.
N.D.C.C. § 1-02-20