National Labor Relations Board v. Pueblo of San Juan , 276 F.3d 1186 ( 2002 )

ON REHEARING EN BANC

HOLLOWAY, Senior Circuit Judge.

In 1996 the San Juan Pueblo tribal council enacted a right-to-work ordinance and also adopted a lease containing similar right-to-work provisions. These actions were challenged by the instant declaratory judgment and injunction suit brought by the National Labor Relations Board (NLRB or the Board) and Local Union No. 1385 of the Western Council of Industrial Workers (the Union) as an intervenor. After rejection of this suit by the district court, the Board and the intervening Union brought this appeal from the district court’s decision granting summary judgment in favor of the Pueblo.

I

The relevant facts are undisputed. San Juan Pueblo is a federally-recognized Indian tribe located in New Mexico. Most of its 5,200 members live on tribal lands that are held in trust by the United States for the Pueblo. The Pueblo is governed by a tribal council, which is vested with legislative authority over tribal lands. Through federally-approved leases, the Pueblo leases certain portions of its tribal land to non-tribal businesses as a source of generating tribal income and as a means of employment for tribal members. The origins of this case lie in a labor dispute involving a lumber company operating on leased lands since August, 1996. The history of the leases as well as the dispute, which has now been settled, is described in the District Court’s opinion. NLRB v. Pueblo of San Juan, 30 F.Supp.2d 1348, 1350-51 (1998).

On November 6, 1996, the San Juan Pueblo Tribal Council enacted Tribal Ordinance No. 96-63 which it amended on February 4, 1998. The ordinance in substance is a so-called “right-to-work” measure. The Pueblo asserts that the ordinance is a valid exercise of its inherent sovereign authority. Id. at 1351. As amended, the ordinance prohibits the making of agreements containing union-security clauses covering any employees, whether tribal members or not. Section 6(a) of the ordinance reads:

No person shall be required, as a condition of employment or continuation of employment on Pueblo lands, to: (i) resign or refrain from voluntary membership in, voluntary affiliation with, or voluntary financial support of a labor organization; (ii) become or remain a member of a labor organization; (iii) pay dues, fees, assessments or other charges of any kind or amount to a labor organization; (iv) pay to any charity or other third party, in lieu of such payments any amount equivalent to or a pro-rata portion of dues, fees, assessments or other charges regularly required of members of a labor organization; or (v) be recommended, approved, referred or cleared through a labor organization.

Supplemental Brief on Rehearing en Banc (NLRB) at 4. The ordinance prohibits employers and unions from entering into agreements requiring employees to maintain membership in or pay dues to a union, called union security agreements. The Pueblo’s lease with the lumber company similarly provides:

Lessee will not enter into any contract or other arrangement which would require a Tribal member to be a member of a union, league, guild, club, or association (hereinafter collectively referred to as “union”) in order to be entitled to all of the priorities to be accorded him pursuant to this Property Lease. Tribal members will not be required to join or maintain membership in, or pay any dues or assessments to, any union in order to be hired and benefit from the priorities stated in this Lease.

Brief on Appeal for the NLRB, at 5. The “priorities” mentioned in the lease refer to terms of employment for employees who are tribal members. Id. at 5 n. 3.

On January 12, 1998, the NLRB filed the instant suit in the United States District Court for the District of New Mexico by its Complaint for Preliminary and Permanent Injunction and for a Declaratory Judgment, alleging that the ordinance and lease provisions, insofar as they prohibit compliance with union-security agreements, are preempted by federal law. Specifically, the Board argued that these provisions are invalid under the Supremacy Clause of the United States Constitution, art. VI, cl. 2,¹ due to preemption by the National Labor Relations Act, 29 U.S.C. §§ 151, et seq. (hereinafter the NLRA). Leave to intervene was granted to the Union upon the parties’ stipulation.

The district court issued a Memorandum Opinion and Order on November 30, 1998, granting the Pueblo’s motion for summary judgment and denying such motions of the NLRB and the Union. NLRB v. Pueblo of San Juan, 30 F.Supp.2d 1348. On appeal, a divided panel affirmed the district court’s decision. We granted petitions of the NLRB and the Union for rehearing en banc which we have held. We now affirm the district court’s decision.

II

A

The Pueblo’s sovereign authority to regulate labor relations and inherent limitations on that authority

The central question before us is whether, in light of the United States Constitution’s Supremacy Clause, and Congress’ plenary power over Indian affairs,² the NLRA prevents the Pueblo from enacting a “right-to-work law” or entering into a lease with provisions making prohibitions similar to those in right-to-work laws.³ We believe the question of the validity of the lease provisions here is subsumed within the larger question of the validity of the ordinance. Because this is a question of law, we review the district court’s order de novo. Mt. Olivet Cemetery Ass’n v. Salt Lake City, 164 F.3d 480, 486 (10th Cir.1998). The burden falls on the NLRB and the Union, as plaintiffs attacking the exercise of sovereign tribal power, “to show that it has been modified, conditioned or divested by Congressional action.” Southland Royalty Co. v. Navajo Tribe, 715 F.2d 486, 488 (10th Cir.1983). As noted in Southland Royalty, “ ‘[a]mbi-guities in federal law have been construed generously in order to comport with ... tribal notions of sovereignty and with the federal policy of encouraging tribal independence.’ ” Id. at 490.

In their challenges to the district court’s decision and our panel’s ruling, the NLRB and the Union argue that § 8(a)(3) of the National Labor Relations Act, 29 U.S.C. § 158(a)(3), clearly protects the rights of a union and an employer to enter into union security agreements meeting the requirements of § 8(a)(3). Moreover the NLRB and the Union maintain that Congress intended by the force of the Wagner and Taft Hartley Acts to preempt state and local regulation of union security clauses with the narrow exception of § 14(b), 29 U.S.C. § 164(b), allowing only states or territories to prohibit otherwise permitted union shop provisions. Appellant’s Opening Brief at 9-10. We disagree and instead are convinced by the Pueblo’s argument that, as an Indian tribe, it retains the sovereign power to enact its right-to-work ordinance, and to enter into the lease agreement with right-to-work provisions, because Congress has not made a clear retrenchment of such tribal power as is required to do so validly.

We begin by noting what the district court also took pains to point out, namely, that the general applicability of federal labor law is not at issue. NLRB v. San Juan Pueblo, 30 F. Supp.2d at 1351. Furthermore, the Pueblo does not challenge the supremacy of federal law. The ordinance, as amended, does not attempt to nullify the NLRA or any other provision of federal law. The suggestion that tribes, including those that have already enacted right-to-work laws,⁴ might “enact ordinances allowing precisely what generally applicable federal law prohibits”⁵ finds no support in this record. Furthermore, there is no danger that the Pueblo and the State of New Mexico might enact conflicting laws, since state right-to-work laws are of no effect in federal enclaves such as Indian reservations, see Lord v. Local Union No.2088, IBEW, 646 F.2d 1057, 1062 (5th Cir.1981) (finding state right-to-work law inapplicable in federal enclave in spite of § 14(b) of the NLRA), cert. denied, 458 U.S. 1106, 102 S.Ct. 3483, 73 L.Ed.2d 1366 (1982); New Mexico Fed’n of Labor v. City of Clovis, 735 F.Supp. 999, 1002-03 (D.N.M.1990) (indirectly noting the inapplicability of state right-to-work laws in federal enclaves).

Rather, the central question here is whether the Pueblo continues to exercise the same authority to enact right-to-work laws as do states and territories, or whether Congress in enacting §§ 8(a)(3) and 14(b) of the NLRA, 29 U.S.C. §§ 158(a)(3) and 164(b), intended to strip Indian tribal governments of this authority as a sovereign. Pursuant to the Supremacy Clause, the federal government has the power to preempt state and municipal authority in a particular field. Wardair Canada, Inc. v. Florida Dep’t of Revenue, 477 U.S. 1, 106 S.Ct. 2369, 91 L.Ed.2d 1 (1986). Likewise, Congress in the exercise of its plenary power over Indian affairs may divest Indian tribes of their inherent sovereign authority, United States v. Wheeler, 435 U.S. 313, 323, 98 S.Ct. 1079, 55 L.Ed.2d 303 (1978), a point the Pueblo does not dispute.

Indian tribes are not states for constitutional purposes, and the preemption analysis is not exactly the same. See Reich v. Mashantucket Sand & Gravel, 95 F.3d 174, 181 (2d Cir.1996) (“[T]ribes are not states under OSHA ... and thus, OSHA does not preempt tribal safety regulations in the same manner in which it preempts state laws.”). We need not delineate precisely the scope of federal preemption of tribal laws here, however. A well-established canon of Indian law states that “statutes are to be construed liberally in favor of the Indians, with ambiguous provisions interpreted to their benefit.” Montana v. Blackfeet Tribe, 471 U.S. 759, 766, 105 S.Ct. 2399, 85 L.Ed.2d 753 (1985). The Supreme Court has also explained that this canon means that “doubtful expressions of legislative intent must be resolved in favor of the Indians.” South Carolina v. Catawba Indian Tribe, 476 U.S. 498, 506, 106 S.Ct. 2039, 90 L.Ed.2d 490 (1986). The canon applies to other statutes, even where they do not mention Indians at all. EEOC v. Cherokee Nation, 871 F.2d 937, 939 (10th Cir.1989) (construing the Age Discrimination in Employment Act).

In resolving questions of preemption of state law, the test is one of congressional intent. Wardair Canada, 477 U.S. at 6, 106 S.Ct. 2369. In order to find preemption of tribal laws, similarly it is necessary to determine whether Congress intended to divest the San Juan Pueblo of its power as a sovereign to pass right-to-work laws. The burden to show such congressional intent to divest the Pueblo of its power to enact its right-to-work ordinance and to enter into the lease agreement rests upon the Union and the NLRB. See EEOC v. Cherokee Nation, 871 F.2d 937, 939 (10th Cir.1989) (requiring party arguing preemption to carry burden of presenting clear evidence of Congressional intent); Southland Royalty Co. v. Navajo Tribe, 716 F.2d 486, 488 (10th Cir.1983) (tribe’s general authority as sovereign included power to tax and the burden on those attacking that power was to show that it had been modified, conditioned or divested by Congressional action). We find no showing here that satisfies the burden of the Board and the Union to demonstrate congressional intent to preempt the Pueblo’s authority to enact the ordinance and enter into the lease agreement. In sum, from §§ 8(3) and 14(b) of the NLRA as they now stand, we find that the Board and the Union are reduced to arguing that there is implied preemption of tribal sovereign authority to enact a right-to-work ordinance or to enter into the challenged lease agreement. However implied preemption of such sovereign authority does not suffice. Iowa Mutual Ins. Co. v. La-Plante, 480 U.S. 9, 18, 107 S.Ct. 971, 94 L.Ed.2d 10 (1987) (“... [T]he proper inference from silence ... is that the sovereign power ... remains intact.”).

Indian tribes are neither states, nor part of the federal government, nor subdivisions of either.⁶ Rather, they are sovereign political entities possessed of sovereign authority not derived from the United States, which they predate. See McClanahan, 411 U.S. at 172, 93 S.Ct. 1257 (“[T]he ... Indian [tribes’] ... claim to sovereignty long predates that of our own Government.”). The Pueblo, like all Indian tribes, need not rely on a federal delegation of powers. “Indian tribes consistently have been recognized ... by the United States, as ‘distinct, independent political communities’ qualified to exercise powers of self-government, not by virtue of any delegation of powers, but rather by reason of their original tribal sovereignty.” Felix Cohen, Handbook of Federal Indian Law 232 (1982) (footnotes omitted) (citing Worcester v. Georgia, 31 U.S. (6 Pet.) 515, 559, 8 L.Ed. 483 (1832)). Tribes retain those attributes of inherent sovereignty not withdrawn either expressly or necessarily as a result of their status. United States v. Wheeler, 435 U.S. 313, 323, 98 S.Ct. 1079, 55 L.Ed.2d 303 (1978). “[U]ntil Congress acts, the tribes retain their existing sovereign powers.” Id. We are persuaded that those powers include the authority to adopt the ordinance challenged here by the .NLRB and the Union and to enter the lease agreement.

In addition to broad authority over intramural matters such as membership, tribes retain sovereign authority to regulate economic activity within their own territory, see, e.g., Merrion v. Jicarilla Apache Tribe, 455 U.S. 130, 137, 102 S.Ct. 894, 71 L.Ed.2d 21 (1982) (recognizing “the tribe’s general authority, as sovereign, to control economic activity within its jurisdiction ... ”); Washington v. Confederated Tribes of the Colville Indian Reservation, 447 U.S. 134, 152-53, 100 S.Ct. 2069, 65 L.Ed.2d 10 (1980) (observing that tribes possess broad civil jurisdiction over the activities of nonmembers on reservation land in which the tribes have a significant interest, and that there was no evidence that Congress had departed from that view). But see Atkinson Trading Co., Inc. v. Shirley, 532 U.S. 645, 121 S.Ct. 1825, 149 L.Ed.2d 889 (2001) (holding that tribal interest in tourism activity by nonmember hotel guests on non-Indian owned land within the reservation was inadequate to support the tribal power to tax).

However, courts have described the tribes’ status as necessarily resulting in the loss of their power to “engage in foreign relations, alienate their lands to non-Indians without federal consent, or prosecute non-Indians in tribal courts which do not accord the full protections of the Bill of Rights.” Colville, 447 U.S. at 153-54, 100 S.Ct. 2069 (citations omitted). Courts have likewise found divestiture of tribal power to tax or regulate certain activities by non-Indians where such activities do not directly affect tribal political integrity, economic security, health, or welfare. See, e.g., Atkinson Trading Co., 532 U.S. 645, 121 S.Ct. 1825, 149 L.Ed.2d 889 (2001) (imposition of hotel occupancy tax on non-Indian guests of non-Indian owned hotel on non-Indian land served by federal and state highways on a reservation); Strate v. A-1 Contractors, 520 U.S. 438, 117 S.Ct. 1404, 137 L.Ed.2d 661 (1997) (civil jurisdiction over a case arising from an accident between nonmembers on a state right-of-way on a reservation); Rice v. Rehner, 463 U.S. 713, 736, 103 S.Ct. 3291, 77 L.Ed.2d 961 (1983) (liquor sales on a reservation, where the federal government and states had long exercised concurrent regulatory authority over such trade); Montana v. United States, 450 U.S. 544, 101 S.Ct. 1245, 67 L.Ed.2d 493 (1981) (non-Indian fishing and hunting on non-Indian land on a reservation).

In general the cases where, absent congressional guidance, tribes have been found to lack regulatory authority have been those involving nonmembers’ activity on non-Indian-owned fee land that was found to have no direct effect on the tribe. “A tribe may regulate, through taxation, licensing, or other means, the activities of nonmembers who enter consensual relationships with the tribe or its members, through commercial dealing, contracts, leases, or other arrangements,” and may also “exercise civil authority over the conduct of non-Indians on fee lands within its reservation when that conduct threatens or has some direct effect on the political integrity, the economic security, or the health or welfare of the tribe.” Montana v. United States, 450 U.S. at 565-66, 101 S.Ct. 1245. See also William Canby, American Indian Law 275-76 (1998) (summarizing recent federal precedents regarding limitations on tribal regulatory jurisdiction). These limiting precedents, however, are not applicable here, where the NLRB seeks a declaratory judgment prohibiting the application of the ordinance to all persons everywhere on the reservation, and where the only instance of regulation cited pertains to consensual commercial dealings between the Pueblo and its members on the one hand, and a lumber company operating on lands leased from the tribe on the other.

B

Whether a valid divestiture has been made of the Pueblo’s sovereign authority to regulate labor relations by enactment of the right-to-work ordinance or adoption of the lease containing right-to-work provisions

The retained sovereign authority of Indian tribes is subject to divestiture by Congress. Divestiture may occur by treaty or statute, United States v. Wheeler, 435 U.S. 313, 323, 98 S.Ct. 1079, 55 L.Ed.2d 303 (1978), the latter being relied on by the Board and the Union here. Divestiture may also occur necessarily as a result of tribal status, id., or where it is “inconsistent with overriding national interests.” Merrion, 455 U.S. at 148 n. 13, 102 S.Ct. 894. However, divestiture is disfavored as a matter of national policy, EEOC, 871 F.2d at 939, and will only be found where Congress has manifested its clear and unambiguous intent to restrict tribal sovereign authority. We have explained that

[w]e believe that unequivocal Supreme Court precedent dictates that in cases where ambiguity exists (such as that posed by the ADEA’s silence with respect to Indians), ... and there is no clear indication of congressional intent to abrogate Indian sovereignty rights (as manifested, e.g., by the legislative history, or the existence of a comprehensive statutory plan), the court is to apply the special canons of construction to the benefit of Indian interests.

Id. (emphasis added).

Indian interests, as the Supreme Court has interpreted them, include tribal sovereignty, see White Mountain Apache Tribe v. Bracker, 448 U.S. 136, 143-44, 100 S.Ct. 2578, 65 L.Ed.2d 665 (1980) (looking to “traditional notions of sovereignty and with the federal policy of encouraging tribal independence” for guidance in interpreting ambiguous or vague federal enactments), and maintaining tribal authority over civil matters on tribal territory, see, e.g., Williams v. Lee, 358 U.S. 217, 223, 79 S.Ct. 269, 3 L.Ed.2d 251 (1959) (upholding a tribe’s authority over a business transaction involving a non-Indian on a reservation, and pointing out that “[t]he cases in this Court have consistently guarded the authority of Indian governments over their reservations”). Doubtful or ambiguous expressions, therefore, are to be construed as leaving tribal sovereignty undisturbed.

The Government has assumed trust responsibility for Indians and tribes, including the pueblos. United States v. Sandoval, 231 U.S. 28, 34 S.Ct. 1, 58 L.Ed. 107 (1913). The canons of construction favoring Indians reflect this. County of Oneida v. Oneida Indian Nation, 470 U.S. 226, 247, 105 S.Ct. 1245, 84 L.Ed.2d 169 (1985) (“The canons of construction applicable in Indian law are rooted in the unique trust relationship between the United States and the Indians.”). Rules of statutory construction generally “provide for a broad construction when the issue is whether Indian rights are reserved or established, and for a narrow construction when Indian rights are to be abrogated or limited.” Cohen at 225. See, e.g., Santa Clara Pueblo v. Martinez 436 U.S. 49, 98 S.Ct. 1670, 56 L.Ed.2d 106 (1978) (construing Indian Civil Rights Act narrowly so as to avoid limiting tribal sovereignty); Bryan v. Itasca County, 426 U.S. 373, 96 S.Ct. 2102, 48 L.Ed.2d 710 (1976) (upholding right of Indians to be free of state taxation in spite of provisions of Public Law 280). We further note that the canon requiring resolution of ambiguities in favor of Indians is to be given the “broadest possible scope,” remembering that “[a] canon of construction is not a license to disregard clear expressions of ... congressional intent.” DeCoteau v. Dist. County Court, 420 U.S. 425, 447, 95 S.Ct. 1082, 43 L.Ed.2d 300 (1975).

Where tribal sovereignty is at stake, the Supreme Court has cautioned that “we tread lightly in the absence of clear indications of legislative intent.” Santa Clara Pueblo, 436 U.S. at 60, 98 S.Ct. 1670. The Court’s teachings also require us to consider tribal sovereignty as a “ ‘backdrop,’ against which vague or ambiguous federal enactments must always be measured,” and to construe “[a]mbiguities in federal law ... generously in order to comport with ... traditional notions of sovereignty and with the federal policy of encouraging tribal independence.” White Mountain Apache, 448 U.S. at 143-44, 100 S.Ct. 2578. Courts are consistently guided by the “purpose of making federal law bear as lightly on Indian tribal prerogatives as the leeways of statutory interpretation allow.” Reich v. Great Lakes Indian Fish & Wildlife Comm’n, 4 F.3d 490, 496 (7th Cir.1993). We therefore do not lightly construe federal laws as working a divestment of tribal sovereignty and will do so only where Congress has made its intent clear that we do so.

Statutes are entitled to the presumption of non-preemption. Maryland v. Louisiana, 451 U.S. 725, 746, 101 S.Ct. 2114, 68 L.Ed.2d 576 (1981). This is especially true in the context of Indian tribal law. As noted, it is well established that federal statutes are to be construed liberally in favor of Indians and tribes, and that any ambiguities or doubtful expressions of legislative intent are to be resolved in their favor. Montana v. Blackfeet, 471 U.S. at 766, 105 S.Ct. 2399; South Carolina v. Catawba, 476 U.S. at 506, 106 S.Ct. 2039. Indian tribes, like states, are entitled to comity. Reich v. Great Lakes Indian Fish & Wildlife Comm’n, 4 F.3d at 496. Furthermore, both the legislative and executive branches have declared that federal Indian policy favors tribal self-government. On this point the Supreme Court has spoken clearly and emphatically: “We have repeatedly recognized the Federal Government’s longstanding policy of encouraging tribal self-government.... This policy reflects the fact that Indian tribes retain attributes of sovereignty over both their members and their territory, to the extent that sovereignty has not been withdrawn by federal statute or treaty.” Iowa Mutual Ins. Co. v. LaPlante, 480 U.S. 9, 14, 107 S.Ct. 971, 94 L.Ed.2d 10 (1987) (internal quotation and citations omitted). See also generally, President’s Message to Congress, The American Indians, 116 Cong.Rec. 23131 (July 8, 1970) (declaring previous termination policy a failure and announcing a new direction in Indian policy, favoring increased tribal autonomy).⁷

The Court has recognized that reservation tribes enjoy the right to “make their own laws and be ruled by them,” as a benefit to be protected from state infringement. Williams, 358 U.S. at 220, 79 S.Ct. 269. Preempting tribal laws divests tribes of their retained sovereign authority, running counter to this policy and not benefitting Indians. See Washington v. Confederated Bands & Tribes of the Yakima Indian Nation, 439 U.S. 463, 484, 99 S.Ct. 740, 58 L.Ed.2d 740 (1979) (stating the “general rule that ambiguities in legislation affecting retained tribal sovereignty are to be construed in favor of the Indians,” i.e., in favor of tribal sovereignty). In the absence of clear evidence of congressional intent, therefore, federal law will not be read as stripping tribes of their retained sovereign authority to pass right-to-work laws and be governed by them.

We turn now to the arguments made by the Board and the Union that Congress has divested the Pueblo of its sovereign authority to enact the right-to-work ordinance and enter into the lease. All parties agree that neither the legislative history of the NLRA, nor its language, make any mention of Indian tribes. We must decide what is the proper inference to draw from this silence. The NLRB cites Andrus v. Glover Constr. Co., 446 U.S. 608, 616-17, 100 S.Ct. 1905, 64 L.Ed.2d 548 (1980): ‘Where Congress explicitly enumerates certain exceptions to a general prohibition, additional exceptions are not to be implied, in the absence of evidence of a contrary legislative intent.” The Board argues that this rule, akin to the well-known principle expressio unius est exclusio alterius, is a “settled principle of statutory construction” which is applicable in this case. Supp. Brief of the NLRB at 16. While this “settled principle” may find application in other types of cases, in matters of Indian law “expressio unius ...” must often be set aside. El Paso Natural Gas Co. v. Neztsosie, 526 U.S. 473, 487, 119 S.Ct. 1430, 143 L.Ed.2d 635 (1999).

The Board argues that, while “ ‘legal ambiguities’ can sometimes be ‘resolved to the benefit of the Indians,’ DeCoteau v. District County Court, 420 U.S. 425, 447, 95 S.Ct. 1082, 43 L.Ed.2d 300 (1975), courts cannot ignore a statute’s plain lan-guage_” Supp. Brief at 17. We disagree, however, with the implied contention that silence establishes this statute’s plain intent to preempt tribal authority. Silence as to tribes can constitute a latent or intrinsic ambiguity that only becomes apparent when other facts are considered. Reich v. Great Lakes Indian Fish & Wildlife Comm’n, 4 F.3d at 493-94. In the context of Indian law, appeals to “plain language” or “plain meaning” must give way to canons of statutory construction peculiar to Indian law. Id. at 493 (finding that the “plain meaning” canon was parried by the canon “that not only treaties but (other) statutes as well are to be construed so far as is reasonable to do in favor of Indians.”). We note further that it is congressional intent, and not merely the naked words of a statute, that controls. South Carolina v. Catawba, 476 U.S. at 507 n. 16, 106 S.Ct. 2039. Silence is not sufficient to establish congressional intent to strip Indian tribes of their retained inherent authority to govern their own territory. See Kerr-McGee Corp. v. Farley, 915 F.Supp. 273, 277 (D.N.M.1995), aff'd 115 F.3d 1498 (10th Cir.1997), cert. denied, 522 U.S. 1090, 118 S.Ct. 880, 139 L.Ed.2d 868 (1998) (observing that congressional silence is to be interpreted in favor of Indians).

The correct presumption is that silence does not work a divestiture of tribal power. Merrion, 455 U.S. at 148 n. 14, 102 S.Ct. 894 (“[T]he proper inference from silence ... is that the sovereign power to tax remains intact.”); El Paso Natural Gas, 526 U.S. 473 at 487, 119 S.Ct. 1430, 143 L.Ed.2d 635 (concluding that tribes should be treated like states because the Price Anderson Act’s silence as to tribes was probably attributable to congressional inadvertence). But see Chickasaw Nation v. United States, 534 U.S. 84, 122 S.Ct. 528, 151 L.Ed.2d 474 (2001) (affirming this circuit’s denial of a tax exemption for tribes on their gaming operations, and reaching this conclusion on the basis of the special canon disfavoring implied tax exemptions, evidence of congressional intent, and strong statutory language); Confederated Tribes of the Warm Springs Reservation v. Kurtz, 691 F.2d 878 (9th Cir.1982) (concluding that express tax exemptions for states, their political subdivisions, and the District of Columbia did not provide the clear statutory guidance required to find a tax exemption for a tribe), cert. denied, 460 U.S. 1040, 103 S.Ct. 1433, 75 L.Ed.2d 792 (1983). In neither of these latter cases, however, was a tribe’s sovereign authority to enact and enforce laws at stake, as is the case here.

The NLRB points out that, “at the time that [§ 14(b)] was enacted, Congress was aware that there existed some twelve States with laws prohibiting union security....”⁸ Supp. Brief (NLRB) at 12. The Board goes on to argue that “the legislative history indicates that it was these State laws which Congress intended to preserve,” and that “[t]he legislative history repeatedly refers to State laws and only State laws prohibiting union security....” Id. However, we are not convinced that Congress did not merely intend to preserve the existing state laws, since in including § 14(b) it recognized the authority of all states — and territories as well — to enact their own right-to-work laws if they wished, not just the twelve states that had already done so. The NLRA embraces the possibility that many of the states might be governed by right-to-work .laws enacted by sovereign governments. Furthermore, the Act embraces diversity of legal regimes respecting union security agreements at the level of “major policy-making units.” New Mexico Fed’n of Labor, 735 F.Supp. at 1003.

Algoma Plywood & Veneer Co. v. Wisconsin Employment Relations Bd., 336 U.S. 301, 69 S.Ct. 584, 93 L.Ed. 691 (1949), is instructive. Algoma arose before the enactment of § 14(b). The Court there held that “§ 8(a)(3) merely disclaims a national policy hostile to the closed shop or other forms of union-security agreement.” Id. at 307, 69 S.Ct. 584. Relying on strong legislative history, the Court quoted from, among others, Senator Wagner, who stated that “[t]he provision will not change the status quo.” Id. at 310, 69 S.Ct. 584 (citations and quotations omitted). The Court concluded that the Wagner Act had not swept aside state authority to regulate union security measures, but was enacted, as to these matters, simply to express Congress’ judgment that closed shops were not illegal where authorized, and not to declare national policy that they were desirable. The Court found this view of § 8(a)(3) supported by the subsequent enactment of § 14(b) in the Tafb-Hartley Act. Id. at 313-14, 69 S.Ct. 584.

Thus the tribe is not preempted by § 8(a)(3) from enacting a right-to-work law for business conducted in its reservation. What Congress has not taken away by § 8(a)(3) it need not give back (by § 14(b)) in order for the tribe to continue to have authority to pass a right-to-work law. Although the Supreme Court has characterized § 8(a)(3) as “articulating] a national policy that certain union-security agreements are valid as a matter of federal law,” Oil, Chemical & Atomic Workers, Int’l Union v. Mobil Oil Corp., 426 U.S. 407, 416, 96 S.Ct. 2140, 48 L.Ed.2d 736 (1976), the Court has also made it clear that § 8(a)(3) was not intended by Congress to be preemptive. See id. at 417, 96 S.Ct. 2140 (noting § 14(b) of the NLRA “was designed to make clear that § 8(a)(3) left the States free to pursue their own more restrictive policies in the matter of union-security agreements”) (internal quotations omitted); Retail Clerks Int’l Ass’n, Local 1625 v. Schermerhorn, 375 U.S. 96, 101, 84 S.Ct. 219, 11 L.Edüd 179 (1963) (noting § 14(b) of the NLRA was enacted to “mak[e] clear and unambiguous the purpose of Congress not to preempt the field”); see also Algoma Plywood, 336 U.S. at 307, 69 S.Ct. 584 (describing the predecessor to § 8(a)(3) as “merely disclaiming] a national policy hostile to the closed shop or other forms of union-security agreement”).

The Court has explained that, in enacting § 14(b), “Congress left the States free to legislate in that field ... [and thus] intended to leave unaffected the power to enforce those laws.” Schermerhom, 375 U.S. at 102, 84 S.Ct. 219 (emphasis added). When Congress enacted § 14(b), it did not grant new authority to states and territories, but merely recognized and affirmed their existing authority. Congress’ silence as to the tribes can therefore hardly be taken as an affirmative divestment of their existing “general authority, as sovereign[s], to control economic activity” on territory within their jurisdictions. See Merrion, 455 U.S. at 137, 102 S.Ct. 894.

Ill

The effect of the Tuscarora case

The NLRB and the Union further urge us to find preemption on the basis of Federal Power Comm’n v. Tuscarora Indian Nation, 362 U.S. 99, 116, 80 S.Ct. 543, 4 L.Ed.2d 584 (1960). There a tribe owned property that the Court held was subject to condemnation under the Federal Power Act in order to create a reservoir. The tribe had been using the property as a reservation,⁹ but the Tuscarora opinion held that Congress had never designated it as such, either by statute or treaty. Id. at 121 n. 18, 80 S.Ct. 543.

The Court noted that Congress appeared to have intended that Act to be generally applicable to “lands owned or occupied by any person or persons, including Indians.” . Id. at 118, 80 S.Ct. 543. The Tuscarora Indian Nation had relied on a rule set out in Elk v. Wilkins, 112 U.S. 94, 5 S.Ct. 41, 28 L.Ed. 643 (1884) that “[gjeneral acts of congress did not apply to Indians, unless so expressed as to clearly manifest an intention to include them.” Tuscarora, 362 U.S. at 116, 80 S.Ct. 543. The Court explained that, although at one time individual Indians had been considered exempt from laws that did not specifically include them, the rule had since been modified. The Court cited Superintendent of Five Civilized Tribes v. Comm’r, 295 U.S. 418, 55 S.Ct. 820, 79 L.Ed. 1517 (1935), in which a restricted¹⁰ Creek Indian’s investment income was held to be subject to federal income tax under the broad terms of the 1928 Revenue Act, and Oklahoma Tax Comm’n v. United States, 319 U.S. 598, 63 S.Ct. 1284, 87 L.Ed. 1612 (1943), in which the State of Oklahoma was held to have authority to impose its nondiscriminatory estate tax on Indians and non-Indians alike. Tuscarora at 116-17, 80 S.Ct. 543. The Court said “it is now well settled by many decisions of this Court that a general statute in terms applying to all persons includes Indians and their property interests.” Id. at 116, 80 S.Ct. 543.

However Tuscarora dealt solely with issues of ownership, not with questions pertaining to the tribe’s sovereign authority to govern the land. Proprietary interests and sovereign interests are separate: One can own land without having the power to govern it by policy determinations as a sovereign, and a government may exercise sovereign authority over land it does not own. Tuscarora mentions no attempts by the tribe to govern the disputed land, nor does it take cognizance of any argument that taking the land would incidentally infringe on tribal sovereign authority to govern. It was the tribe’s possessory interest in the land, rather than its sovereign authority to govern activity on the land, that was at stake in Tuscarora. The Tuscarora Court’s remarks concerning statutes of general applicability were made in the context of property rights, and do not constitute a holding as to tribal sovereign authority to govern.

In Phillips Petroleum, Co. v. U.S. Environmental Protection Agency, 803 F.2d 545 (10th Cir.1986), we dealt with property rights and reached the conclusion that tribal ownership did not prevent a generally applicable federal statute from regulating activity to ensure the safety of ground water under tribally-owned land. There, the Osage tribal government’s property interest was regulated by the Safe Drinking Water Act of 1974 (SDWA), but its sovereign authority was not. Far from attempting to exercise its sovereign authority to enact a competing regulation, the tribe supported the federal regulation and indicated its approval by tribal resolution; it was a third party (Phillips Petroleum) that challenged the application of the regulation. Id. at 556. Furthermore, the facts differ significantly between that case and the instant one. There, the statute gave delegated authority to the Environmental Protection Agency to promulgate regulations governing underground injection, which threatened to pollute groundwater and endanger the nation’s drinking water supply. Id. at 547-48.

Other cases have applied the Tuscarora principle to Indian tribal governments acting in proprietary capacities. See, e.g., Florida Paraplegic Ass’n, Inc. v. Miccosukee Tribe of Indians of Florida, 166 F.3d 1126 (11th Cir.1999); Reich v. Mashantucket Sand & Gravel, 95 F.3d 174 (2d Cir.1996); Smart v. State Farm Ins., 868 F.2d 929 (7th Cir.1989); and Donovan v. Navajo Forest Products Industries, 692 F.2d 709 (10th Cir.1982).

Thus Tuscarora is not persuasive here. We are convinced it does not apply where an Indian tribe has exercised its authority as a sovereign — here, by enacting a labor regulation — rather than in a proprietary capacity such as that of employer or landowner. In spite of the Board’s attempts to bring to our attention multiple cases where the rule was applied to a tribe qua sovereign, no citations were found to be apposite.¹¹ Supp. Brief of the Board at 23 n. 22. Further, Tuscarora does not control where, as here, the law is not generally applicable as the exceptions of § 14(b) show. The exception to § 8(a)(3) recognized in § 14(b) indicates that Congress did not intend “inclusion within its general ambit as the norm,” Smart, 868 F.2d at 933. In view of Congress’ intention with regard to this statute, and the federal policy that has long recognized tribal sovereignty, we do not think that Tuscarora may be applied to divest a tribe of its sovereign authority without clear indications of such congressional intent which are lacking here. We therefore are convinced that § 8(a)(3)’s proviso permitting union security agreements does not support divestment of the Pueblo’s sovereign authority to enact the right-to-work ordinance.

The exemption of § 8(a)(3) contemplates that federal law, and particularly the provisions of § 8(a)(8), may conflict with that of other sovereigns, but intends that federal law give way. Oil, Chemical & Atomic Workers, 426 U.S. at 417, 96 S.Ct. 2140, (recognizing “a conflict sanctioned by Congress with directions to give the right of way to state l|ws.”). We recognize that § 14(b) should not be read as granting states and territories general power to supplant federal labor law; states and territories may not, for instance, enact laws that exempt their territory from other federal labor regulations. See id. at 418 n. 7, 96 S.Ct. 2140 (finding no suggestion in § 14(b)’s language or legislative history that types of laws not mentioned in § 14(b) might be permissible). However neither the Board nor the Union contests the Pueblo’s assessment of its right-to-work law as being similar to state right-to-work laws. Brief for Appellee Pueblo of San Juan at 6. There is therefore no showing before us that the Pueblo’s right-to-work ordinance is a kind of law that a state or territory might not be permitted to enact and enforce.

Like states and territories, the Pueblo has a strong interest as a sovereign in regulating economic activity involving its own members within its own territory, and it therefore may enact laws governing such activity. Merrion, 455 U.S. at 137, 102 S.Ct. 894. Merrion illustrates the exercise of sovereign authority (there, to tax) and that sovereign authority exercised was recognized to be “a fundamental attribute of sovereignty which the tribes retain unless divested of it by federal law or necessary implication of their dependent status.” Id. at 137, 102 S.Ct. 894 (quoting Washington v. Confederated Tribes of Colville Indian Reservation, 447 U.S. 134, 152, 100 S.Ct. 2069, 65 L.Ed.2d 10 (1980)). The legislative enactment of the Pueblo’s right-to-work ordinance was also clearly an exercise of sovereign authority over economic transactions on the reservation. This distinguishes the Pueblo’s exercise of sovereign authority here from a congressional enactment like that in Tuscarora which did not affect tribal legislative policy but instead impacted proprietary interests. This distinction demonstrates why the Tuscarora principle, that Indians’ proprietary interests may be affected even when Indians are not specifically mentioned, does not apply here where the matter at stake “is a fundamental attribute of sovereignty” and “a necessary instrument of self-government and territorial management ... [which] derives from the tribe’s general authority, as sovereign, to control economic activity within its jurisdiction.” Merrion, 455 U.S. at 137, 102 S.Ct. 894.

IV

In sum, we are convinced that Congress did not intend by its NLRA provisions to preempt tribal sovereign authority to enact its right-to-work ordinance and to enter into the lease agreement. The Board and the Union had the burden to establish such intent of preemption, but they did not satisfy their burden. Since they failed to do so, we uphold the tribal right-to-work ordinance. Similarly we see no reason to hold invalid the lease provisions entered into by the Tribe. Accordingly, the decision of the district court is

AFFIRMED.

1 . "This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the Supreme Law of the Land; and the Judges in every State shall be bound thereby, anything in the Constitution or Laws of any State to the Contrary notwithstanding.” United States Constitution, art. VI, cl. 2.

2 . Congress’ power over Indian matters derives from the Constitution's Indian Commerce Clause, in art. I, § 8, cl. 3, and its treaty power, art. II, § 2, cl. 2. McClanahan v. Arizona State Tax Comm’n, 411 U.S. 164, 172 n. 7, 93 S.Ct. 1257, 36 L.Ed.2d 129 (1973).

3 . A "right-to-work” law, as the term is used here, is a statute which § 14(b) of the NLRA permits states and territories to enact to invalidate agreements establishing "union shops.” A closed shop, originally permitted under the NLRA, is created when an employer and a union agree that only people who are already union members may be hired. This was outlawed in 1947 by the Taft Hartley Act's amendment of the NLRA, 29 U.S.C. § 158(a)(3). A union shop is created when an employer and a union agree to require employees, as a condition of their continued employment, to have membership in a labor union "on or after the thirtieth day following the beginning of such employment.” 29 U.S.C. § 158(a)(3). Such an agreement between an employer and a union is a union security agreement. Provided they comply with other requirements of 29 U.S.C. § 158, and provided no right-to-work law forbids them, the NLRA permits union shops and union security agreements.

4 . These include the Navajo Nation, the Crow Tribe, and the Osage Tribe. Amicus Curiae brief of the National Right to Work Foundation in Support of Appellee Pueblo of San Juan at 17.

5 . NLRB brief at 12.

6 . As we have previously explained,

Indian tribes are not states. They have a status higher than that of states. They are subordinate and dependent nations possessed of all powers [except] to the extent that they have expressly been required to surrender them by the superior sovereign, the United States.

Native Am. Church of N. Am. v. Navajo Tribal Council, 272 F.2d 131, 134 (10th Cir.1959).

7 . This address by President Nixon has been identified as having "clearly set the current direction of federal policy.” William Canby, American Indian Law 30 (1998) (citing Cong. Rec. 23258).

8 . On September 25, 2001, Oklahoma voters approved a state right-to-work question, bringing the total to 22 such states.

9 . The lands involved were owned in fee simple by the Tuscarora Indian Nation and no "interest” in them was "owned by the United States” so that they were not within a “reservation” as that term was defined in § 3(2) of the Federal Power Act.

10 . In keeping with the guardian-ward relationship, the allotted property of certain Indians was subject to the supervision of the United States and could not be freely alienated. They were referred to as "restricted” Indians. See Chouteau v. Comm'r of Internal Revenue, 38 F.2d 976, 977 (10th Cir.1930) (plaintiff Mary Blackbird "is a restricted full-blood Osage. Her property is under the supervising control of the United States.”). See also Cohen at 650-51 (discussing restrictions).

11 . In Tuscarora, 362 U.S. 99, 80 S.Ct. 543, 4 L.Ed.2d 584, the rule was applied to the tribe as a property owner and not as a sovereign authority. In Nero v. Cherokee Nation of Oklahoma, 892 F.2d 1457, 1462-63 (10th Cir.1989), we found that a generally applicable rule did not apply to the tribe as sovereign.