N.D. Cent. Code § 14-05-08: Abuse of alcohol or controlled substances defined

Abuse of alcohol or controlled substances is that degree of use which disqualifies the person a great portion of the time from properly attending to business or which reasonably would inflict a course of great mental anguish upon the innocent party. For purposes of this chapter, "controlled substance" means a substance as defined in section 19-03.1-01.