Indian Nondiscriminatory Tax Act

Indian Nondiscriminatory Tax Act - Requires the Secretary of the Interior's approval of all new tribal taxation ordinances.

Prohibits the Secretary from approving a tribal taxation ordinance unless: (1) with respect to a property tax, it does not discriminate between Indians and non-Indians; and (2) it has a reasonable relationship to the services rendered.

Provides for an 80 percent offset against a tribal tax for State and local taxes on the same property.

Requires a tribal tax to be assessed within five years after the date imposed. Prohibits commencement of a proceeding a tribal court without assessment for collection of such tax after such period has expired.