North dakota constitution
Article XV: term limits
Section 1

An individual shall not serve as a member of the house of representatives for a cumulative period of time amounting to more than eight years. An individual shall not serve as a member of the senate for a cumulative period of time amounting to more than eight years. An individual shall not be eligible to serve a full or remaining term as member of the house of representatives or the senate if serving the full or remaining term would cause the individual to serve for a cumulative period of time amounting to more than eight years in that respective house.