I. Tribal Authority to Manage Air Quality

Indian tribes can undertake air quality programs either under the inherent power of a sovereign Tribal government or pursuant to the Clean Air Act. Indian tribes were independent, self-governing societies long before contact with European nations. The United States recognizes tribes as "distinct, independent political communities" qualified to exercise powers of self-government by reason of their original tribal sovereignty.

Under well-established principles of Federal Indian law, a tribe retains attributes of sovereignty over both its lands and its members. Further, tribes retain the "inherent authority necessary to self-government and territorial management" and there is a significant territorial component to tribal power. The Court has recently summarized these principles by recognizing that retained inherent tribal authority extends "to managing tribal land."

A tribe also retains its well-established traditional power to exclude nonmembers from tribal land, including "the lesser power to place conditions on entry, on continued presence, or on eservation conduct." On tribal trust lands, a tribe can regulate the conduct of persons over whom it could "assert a landowner’s right to occupy and exclude."

The Supreme Court, however, has erected some significant constraints on the ability of a tribe to exercise its inherent tribal authority over persons who are not members of the tribe. In Montana v. United States, the Supreme Court found that absent a Federal grant of authority, tribes generally lack jurisdiction over nonmember activities on nonmember fee land with two exceptions: First, when nonmembers enter into "consensual relationships with the tribe or its members, through commercial dealing, contracts, leases, or other arrangements;" or second, when "…[nonmember] conduct threatens or has some direct effect on the political integrity, the economic security, or the health or welfare of the tribe." In analyzing Tribal assertions of inherent authority over nonmember activities on fee lands on Indian reservations, the Supreme Court has reiterated that Montana remains the relevant standard.

The judicially created limitations that have been placed on a tribe’s inherent authority become important if the tribe wishes to establish civil requirements under tribal law that would be enforced against both members and nonmembers in tribal court. The series of court decisions noted here present significant issues to Indian tribes whose reservations are populated in part by nonmembers who are living on privately owned land located within the reservation boundaries and interspersed with trust lands, which are often referred to as "checkerboarded" reservations.

The CAA offers a powerful alternative for tribes who want to become involved with air quality management but do not want to rely solely on exercising the tribe’s inherent tribal authority. Under Section 301(d) of the Act, tribes may develop air programs covering their reservations and non-reservation areas within their jurisdiction for submission to EPA for approval in the same manner as States develop air quality programs for EPA approval. EPA published a rule in 1998, generally referred to as the "Tribal Authority Rule" or "TAR," that established how EPA can approve tribal TAS eligibility applications for a tribe to operate a CAA program under tribal law using a modular approach. It is EPA's position that Section 301(d) of the CAA constitutes a statutory delegation of Federal authority to eligible tribes over their reservations. Therefore, pursuant to Section 301(d) of the CAA, tribes can exercise tribal authority as approved by EPA over both Indian and non-Indian sources within an Indian reservation. Section 110(o) of the Act clarifies that after EPA approves a Tribal Implementation Plan or "TIP" of a Tribe which has been adopted under the tribe’s laws, the plan will apply to all sources within the exterior boundaries of the Tribe’s reservation regardless of land ownership.