OPINION
MARTONE, Justice.¶ 1 In State v. Zaman, 190 Ariz. 208, 946 P.2d 459 (1997), cert. denied, — U.S.-, 118 S.Ct. 1167, 140 L.Ed.2d 177 (1998), we held that the superior court has jurisdiction over an action brought by the state against a non-Indian father to determine paternity, custody, and child support obligations. We vacated the contrary opinion of the court of appeals. On remand, the court of appeals held that a county sheriff could not serve process on a non-Indian within the boundaries of the reservation. State v. Zaman, 261 Ariz. Adv. Rep. 28, No. 1 CA-CV 94-0259, 1998 WL 25559 (App. Jan. 27, 1998). We granted review and again vacate the opinion of the court of appeals.
¶2 In reaching its conclusion, the court of appeals relied upon Francisco v. State, 113 Ariz. 427, 556 P.2d 1 (1976), and Dixon v. Picopa Construction Co., 160 Ariz. 251, 772 P.2d 1104 (1989). But each of these cases held that a sheriff could not serve process on an Indian while the Indian was on his tribe’s reservation. These cases have no application to the question of whether a sheriff may serve process on a non-Indian. For on-reservation activities, the status of the defendant as an Indian or non-Indian is the sine qua non of federal Indian law. See, e.g., Oliphant v. Suquamish Indian Tribe, 435 U.S. 191, 98 S.Ct. 1011, 55 L.Ed.2d 209 (1978)(holding tribe does not have jurisdiction over crimes committed by non-Indians on the reservation); McClanahan v. Arizona State Tax Comm’n, 411 U.S. 164, 93 S.Ct. 1257, 36 L.Ed.2d 129 (1973) (holding state *443has no power to tax income of Indian from on-reservation sources); United States v. McBratney, 104 U.S. 621, 26 L.Ed. 869 (1881) (holding state has jurisdiction over crimes committed by non-Indian against non-Indian on the reservation); 18 U.S.C. §§ 1152-53 (granting federal jurisdiction over crimes committed by Indians against non-Indians and by non-Indians against Indians on the reservation and over major crimes committed by Indians on the reservation). Indeed, were it not for this distinction, federal Indian law, as we know it, would not exist. See generally, Felix S. Cohen, Handbook of Federal Indian Law (1982 ed.).
¶3 The Supreme Court of the United States held over 100 years ago that when a state has civil jurisdiction over a non-Indian, it has jurisdiction to serve process on that non-Indian on a reservation. Langford v. Monteith, 102 U.S. 145, 147, 26 L.Ed. 53, 54 (1880) (a reservation within a territory is “subject to [territorial] jurisdiction, so that process may run there, however the Indians themselves may be exempt from that jurisdiction”); see Organized Village of Kake v. Egan, 369 U.S. 60, 72, 82 S.Ct. 562, 569, 7 L.Ed.2d 573 (1962); see also William C. Canby, Jr., American Indian Law 151 (2d ed. 1988) (“State courts have jurisdiction over suits by non-Indians against non-Indians, even though the claim arose in Indian country, so long as Indian interests are not affected. State court process may be served in Indian country in connection with such a suit.”).
¶ 4 We hold that service of process by the sheriff on a non-Indian within that part of the reservation within Arizona is valid. This would ordinarily conclude our opinion, but the theory advanced by the dissent warrants consideration.
¶ 5 The dissent argues that the rationale of Francisco can be extended to non-Indians, and goes so far as to claim that McClanahan v. State Tax Commission, 411 U.S. 164, 93 S.Ct. 1257, 36 L.Ed.2d 129 (1973), supports that extension. See post, at ¶¶ 21-22. On the contrary, the question in McClanahan was “whether the State may tax a reservation Indian for income earned exclusively on the reservation.” McClanahan, 411 U.S. at 168, 93 S.Ct. at 1260 (emphasis added). The Court went out of its way to state that it was not “concerned with exertions of state sovereignty over non-Indians who undertake activity on Indian reservations.” Id. (emphasis added). Indeed, the Court noted that actions by Indians against non-Indians in state courts have been sanctioned, that the Williams v. Lee infringement test applies to “situations involving non-Indians,” and that “[t]he problem posed by this case is completely different----[s]ince appellant is an Indian and since her income is derived wholly from reservation sources____” Id. at 171, 179, 93 S.Ct. at 1262, 1266.
¶ 6 That the McClanahan bar to the assertion of state jurisdiction applied to Indians was acknowledged in Francisco. We noted that in McClanahan the Court found that “the ability of Arizona to impose an income tax on Indians ” was preempted. Francisco, 113 Ariz. at 429, 556 P.2d at 3 (emphasis added). We applied preemption in Francisco so “the Executive Order would preclude the extension of state law to Indians on the reservation, including the laws which effectuate the authority in the Sheriff to serve process.” Id. at 430, 556 P.2d at 4 (emphasis added).
¶ 7 The dissent cites a student’s law review note that suggests that the reservation may be out-of-state for service of process purposes. See post, at ¶ 22. But the argument was limited to “the extension of state law to reservation Indians,” not to non-Indians. Note, Service of Process on Indian Reservations: A Return to Pennoyer v. Neff, 18 Ariz. L.Rev. 741, 750 (1976) (emphasis added). Indeed, the note concludes by criticizing Francisco for not holding that the reservation was out-of-state as to Indians. Id. at 756.
¶ 8 Nor does the dissent’s reference to Public Law 280, codified at 25 U.S.C. § 1322, advance its argument. See post, at ¶22. Public Law 280 has nothing to do with the state’s assertion of power over a non-Indian. Public Law 280 is “a method whereby States may assume jurisdiction over reservation Indians.” McClanahan, 411 U.S. at 177, 93 S.Ct. at 1265 (emphasis added). Arizona does not need Public Law 280 to extend its *444laws to non-Indians within the boundaries of a reservation.
¶ 9 The reference to Professor Laurence’s piece is no more helpful to the dissent’s position. See post, at ¶ 22. Professor Laurence’s entire article was addressed to service of state process on an Indian on a reservation for off-reservation activity. That is why Professor Laurence referred to Public Law 280 which, as explained, has no applicability here.
¶ 10 So, too, the dissent’s reliance on Dixon v. Picopa Construction Co., 160 Ariz. 251, 772 P.2d 1104 (1989), is misplaced. See post, at ¶ 23. In Dixon, we said “[i]n Francisco, we held that a deputy sheriff had no authority to serve process on an Indian while the Indian is on his tribe’s reservation.” 160 Ariz. at 259, 772 P.2d at 1112 (emphasis added). And Dixon’s use of the “out-of-state” metaphor involved an attempt to serve process on an Indian for his off-reservation activities, not a non-Indian. Id. at 259-60, 772 P.2d at 1112-13.
¶ 11 The dissent says that Langford v. Monteith is not dispositive. See post, at ¶ 24. But under the Supremacy Clause, Langford v. Monteith is “the supreme law of the land; and the judges in every state shall be bound thereby.” U.S. Const. art. VI; see, e.g., Arizona Dep’t of Revenue v. Blaze Constr. Co., 526 U.S. 32, 119 S.Ct. 957, 960, 143 L.Ed.2d 27 (1999) (“We have never employed this balancing test in a case such as this one where a State seeks to tax a transaction between the Federal Government and its non-Indian private contractor.” (emphasis added)), rev’g State v. Blaze Constr. Co., 190 Ariz. 262, 947 P.2d 836 (App.1997).
¶ 12 The argument that Langford can be distinguished because of language in the Navajo treaty is foreclosed by both McClanahan and Francisco. McClanahan limited the effect of the treaty language “to preclude extension of state law — including state tax law — to Indians on the Navajo Reservation.” 411 U.S. at 175, 93 S.Ct. at 1264. And in Francisco we said that similar language in Arizona’s enabling act “in no way precludes the state from exercising its governmental interest by way of service of process on an Indian on a reservation.” 113 Ariz. at 430, 556 P.2d at 4. Indeed, we reaffirmed the holding of Porter v. Hall, 34 Ariz. 308, 321, 271 P. 411, 415 (1928), that our enabling act disclaimed “only the state’s proprietary interest in Indian lands and not its governmental interest,” id., and that “all Indian reservations in Arizona are within the political and governmental, as well as geographical, boundaries of the state.” Id. (quoting Porter, 34 Ariz. at 321, 271 P. at 415).
¶ 13 The expansive approach advanced by the dissent fails to acknowledge that the reservation is within Arizona — not outside it. Members of the tribe who reside on that part of the reservation in Arizona are citizens of Arizona, not New Mexico or Utah.
¶ 14 The dissent next suggests that the state could have used Rule 4(c) of the Navajo Rules of Civil Procedure, to serve process within the boundaries of the reservation. See post, at ¶ 25. But that rule applies only to proceedings in the Navajo tribal courts. Proceedings in the Superior Court of Arizona are governed by the Arizona Rules of Civil Procedure.
¶ 15 Finally, the dissent quotes Cohen’s Handbook of Federal Indian Law to suggest that state service “generates needless friction with the tribes and is poor policy.” Post, at ¶ 27. But the Cohen quotation refers to service by a sheriff in an action in which “a state court has subject matter jurisdiction over a claim against an Indian.” Felix S. Cohen, Handbook of Federal Indian Law 361 (1982 ed.)(emphasis added). Service on an Indian within the boundaries of a reservation is one thing; service on a non-Indian is quite another. The distinction is central to federal Indian law.
¶ 16 We decided the question of comity against Zaman’s position in our first opinion. Zaman, 190 Ariz. at 212-13, 946 P.2d at 463-64. We explained why state court jurisdiction was certain and tribal court jurisdiction was uncertain at best. Comity is a doctrine that could have been considered if the tribal court had subject matter jurisdiction. But, absent an intergovernmental agreement of some kind, service of state court process by a tribal police officer would likely violate state law. In our first Zaman opinion, we said *445“we believe it would be unwise to hold that the state court should refrain from exercising certain state court jurisdiction in favor of uncertain tribal court jurisdiction.” Id. at 213, 946 P.2d at 464. The same is true of service of process. State service of process was valid here. This case affords us no opportunity to explore the limits of comity in other settings.
¶ 17 It is plain, therefore, that service of process by the sheriff on a non-Indian was both lawful and effective to allow the superi- or court to exercise in personam jurisdiction over Zaman.1 We vacate the opinion of the court of appeals. Having resolved all issues raised on appeal, we affirm the judgment of the superior court.
CONCURRING: RUTH V. McGREGOR, Justice.. Having concluded that service of process was defective, the court of appeals said that it did not have to reach Zaman's separate argument that he had insufficient contacts with Arizona to allow Arizona to assert in personam jurisdiction over him. We have examined the briefs and conclude that this argument has insufficient merit to warrant discussion. To the extent that it has not already been resolved by our first opinion in this case, we summarily reject it.
. Act of Aug. 15, 1953, ch. 505, 67 Stat. 588, currently codified at 25 U.S.C. §§ 1321-26. *446Adopting the law would have required Arizona to appropriately amend its statutes or constitution, and now requires the consent of the Indian tribe. See Francisco, 113 Ariz. at 430, 556 P.2d at 4.