N.D. Cent. Code § 47-16-07.5
A landlord may require reliable supporting documentation be provided by a tenant of a rental dwelling that is subject to a no pets policy, if the tenant asserts a disability requiring a service animal or assistance animal be allowed as an accommodation on the rented premises under any provision of law. Reliable supporting documentation may be provided by a physician or medical professional who does not operate in this state solely to provide certification for service or assistance animals. Reliable supporting documentation must confirm the tenant's disability and the relationship between the tenant's disability and the need for the requested accommodation. A landlord may not require supporting documentation from a tenant if the tenant's disability or disability-related need for a service animal or assistance animal is readily apparent or already known to the landlord.
N.D.C.C. § 47-16-07.5