Decision 9 G.R. No. 221139 Additionally, a writ of mandamus, as with certiorari and prohibition, shall be issued only upon a showing that "there is no other plain, speedy[,] and adequate remedy in the ordinary course of law[.]" 41 III Petitioner anchors his plea on Section 65 of the Indigenous Peoples' Rights Act, which reads: SECTION 65. Primacy of Customary Laws and Practices. When disputes involve ICCs/IPs, customary laws and practices shall be used to resolve the dispute. Falling under Chapter IX of the Indigenous Peoples' Rights Act, Section 65 is part of a larger framework on "Jurisdiction and Procedures for Enforcement of Rights." This framework enables the application of customary laws and practices in dispute resolution for indigenous peoples. Section 6642 builds on Section 65. It indicates that disputes still unresolved despite the exhaustion of remedies under customary laws governing the parties belonging to the same indigenous cultural community may be brought to the National Commission on Indigenous Peoples. 43 Further building on Sections 65 and 66, Section 67 states that "[ d]ecisions of the [National Commission on Indigenous Peoples] shall be appealable to the Court of Appeals by way of a petition for review." The provisions under Chapter IX do not only lend legitimacy to and enable the continuing efficacy and viability of customary laws and practices to maintain order and dispense justice within indigenous cultural communities. They also work to segregate customary laws and practices in two (2) respects. First, they make customary laws and practices structurally and operationally distinct from enactments of the legislature and of those upon whom legislative power has been delegated, as well as regulations of general application. Second, they distinguish disputants belonging to the 41 42 43 RULES OF COURT, Rule 65, sec. 3. Rep. Act No. 8371 (1997), sec. 66 provides: SECTION 66. Jurisdiction of the NCIP. - The NCIP, through its regional offices, shall have jurisdiction over all claims and disputes involving rights of ICCs/IPs: Provided, however, That no such dispute shall be brought to the NCIP unless the parties have exhausted all remedies provided under their customary laws. For this purpose, a certification shall be issued by the Council of Elders/Leaders who participated in the attempt to settle the dispute that the same has not been resolved, which certification shall be a condition precedent to the filing of a petition with the NCIP. Unduran v. Aberasturi (771 Phil. 536 (2015) [Per J. Peralta, En Banc]) settled that: [P]ursuant to Section 66 of the IPRA, the NCIP shall have jurisdiction over claims and disputes involving rights of ICCs/IPs only when they arise between or among parties belonging to the same ICC/IP. When such claims and disputes arise between or among parties who do not belong to the same ICC/IP, i.e., parties belonging to different ICC/IPs or where one of the parties is a non-ICC/IP, the case shall fall under the jurisdiction of the proper Courts of Justice, instead of the NCIP. I