The Multiple Roles of Socio-Anthropological Expert Evidence in Indigenous Land Claims: The Xukuru People Case

ABSTRACT In 2018, the Inter-American Court delivered the first – and so far, only – judgment against Brazil on Indigenous land rights. This leading decision upheld the state’s failure to comply with human rights obligations due to the non-removal of non-Indigenous individuals from the territory of the Xukuru people. Such an issue, namely, insecure land tenure affects Indigenous peoples worldwide. The decision’s outcome consolidated a critical trend in international law concerning the concept of Indigenous lands: a place where Indigenous peoples have their residence and holistically develop their life, which states must actively protect, according to Article 21 of the American Convention read in conjunction with Article 1.1 and 2 thereof. By analyzing secondary sources (inter alia, ethnographies and court documents), this paper addresses the role of social (or cultural) anthropology regarding expert evidence in the Xukuru land claims. It articulates the Brazilian and Inter-American legal framework on expert evidence and Indigenous land rights with the literature on ‘anthropological expertise’ and ‘cultural expertise’, which includes the branches of forensic social anthropology and expert social anthropology. This analysis underscores the evolving challenges concerning expert evidence in legal-administrative procedures on the national and international levels. It argues that cultural anthropologists acting as experts on these levels need different sets of skills, which should be developed through special training. Thus, this paper amplifies the interdisciplinary dialogue between law and social anthropology on the topical issue of human rights adjudication.


Introduction
Indigenous peoples' advocacy has played a groundbreaking role in Brazil's constitutional-making process (Krenak 2012, 122-124;Pataxó 2021, 82-84).Chief Xikão Xukuru was a leading figure there and contributed to developing innovative aspects regarding Brazilian constitutional law, including normative elements associated with multicultural citizenship, and the current legal framework on the rights of Indigenous peoples.However, his extraordinary political commitment cost him his life.A decade after the Constitution's promulgation, in 1998, he was murdered while defending the implementation of Indigenous land rights. 1 His death seriously impacted the communal life of his people, the Xukuru of Ororubá, 2 who decided to plant his body in a sacred place so that new fighters like him could flourish in the Xukuru land (Figueiroa 2011, 182-183;Xikão Xukuru 2008, pt. 12:06-12:18).
The assassination of Chief Xikão Xukuru was a turning point in the history of the Xukuru people.On the one hand, the grief, fear, and sense of injustice severely damaged the community's motivation to continue the struggle for their land.Xikão was a charismatic leader who carried within himself the representation of the sacred for his people (Inter-American Court of Human Rights 2017, 50).On the other hand, Xikão's assassination marked the beginning of the so-called 'institutional criminalization of the Xukuru' (Fialho 2011, 11), a phenomenon evidenced by the increase in violence (moral, psychological, and physical) against the Xukuru and their leaders, which was aggravated by the insecure land tenure.Xukuru's collective social organization was seriously shaken, particularly as the Brazilian state, through the Public Prosecutor's Office, prosecuted Indigenous leaders and then, wrongly convicted to prison some of them, including Chief Xikão's successor and current leader of the Xukuru people, Chief Marcos Xukuru. 3Without the guarantee of their land rights, members of the Xukuru people have found themselves in a situation of extreme vulnerability, which has ultimately led to the murder of other members and leaders of the Xukuru, such as Chico Quelé.
After a necessary and challenging internal political reconfiguration, the Xukuru people continued with their chief's work.They recently achieved a new milestone by persisting in the historical battle for their territory (Oliveira, Maria Neves, and Fialho 2022, 439).In 2018, the Inter-American Court of Human Rights (hereinafter IACtHR) delivered the firstand so far, onlyjudgment against Brazil on Indigenous land rights (Inter-American Court of Human Rights 2018).This leading decision upheld the state's failure to comply with human rights obligations due to the non-removal of non-Indigenous individuals from the territory of the Xukuru people.This matter (i.e.insecure land tenure) affects Indigenous peoples worldwide, which reinforces the relevance of IACtHR's judgment on the Xukuru case, particularly for expanding international legal standards.Likewise, the decision's outcome consolidated a critical trend in international law concerning the concept of Indigenous lands that employs anthropological notions: a place where Indigenous peoples have their residence and holistically develop their life, which states must actively protect, according to Article 21 (Right to Property) of the American Convention on Human Rights (hereinafter ACHR) read in conjunction with Article 1.1 (Obligation to Respect Rights) and 2 (Domestic Legal Effects) thereof.Thus, Indigenous land rights are intrinsically connected to other rights, such as life, self-determination, and economic, social, and cultural rights.
To issue this judgment, the IACtHR had to scrutinize the 'demarcation of an Indigenous land', a standard step in South American legal-administrative procedures that is vital for protecting Indigenous peoples' territorial rights (Aylwin 2014, 47).As discussed below, demarcation consists of setting the geographical limits of a given Indigenous land through a procedure based on scientific evidence with the scope of issuing the respective land title.In examining it, the Inter-American judges engaged with other disciplines, given that 'Indigenous land' is an interdisciplinary concept per nature that contrasts with the notion of individual property.'You are the life, the magic and the mystery, the silence and the majesty of the Cordillera, and the sound of my voice' (Pachamama 2020), 4 says a poem written by Churiah of the Puri People (Brazil) that beautifully reveals the special meaning of lands for Indigenous peoples regarding their non-tangible dimensions (i.a., religious and cultural ones).
Cultural anthropologists (hereinafter anthropologists) and their expertise (hereinafter anthropological expertise) are essential for conducting demarcation procedures, which are usually based on expert reports.These procedures are the subject of ever-evolving debates in sociocultural anthropological scholarship (hereinafter anthropological scholarship), especially due to growing economic pressures on Indigenous territories that raise various forms of academic challenges for anthropologists, including ethical and methodological ones, such as the creation of analytical tools for elaborating Indigenous territorial maps through participatory demarcation procedures.The analysis of the Xukuru case is vital to update these debates.
The uniqueness of the case at hand is that anthropological expertise was sought to adjudicate land rights internationallysomething novel for Brazilian-trained anthropologists and unusual before human rights courts.As discussed below, the international legal proceedings in the present case raised new challenges for anthropologists and legal practitioners.The IACtHR's judges examining the complaint were unfamiliar with the Brazilian context of Indigenous land tenure and its legal framework since they were from other South American countries, including Mexico, Chile, and Colombia.Due to their unfamiliarity and the complexity of the matter at hand, experts could play a significant role in the lawsuit, informing the reasons behind the judgment, if they matched the sophisticated (formal and informal) requirements of Inter-American evidence-making.
Likewise, the official public hearing counted on the state-appointed expert testimony of Christian Teófilo, a professor at a leading university in Brazil and an anthropologist with international credentials, as a member of both the Brazilian Association of Anthropologists (hereinafter BAA) and the Canadian Society of Anthropology.Interesting is that he could not be regarded as an expert on Xukuru land issues since he did not have a track record of ethnographical fieldwork with the Xukuru people, but at that time, he was working as an expert for the attorney general's office for the federal government (Advocacia Geral da União) and thus, he was indicated. 5During his cross-examination, Mrs. Vânia Fialho, an anthropologist and professor who is famous for her work with the Xukuru people, appeared on behalf of the opposite party (the representatives of the victims).Despite the state's objections, she asked Teófilo challenging questions that demonstrated her expertise on the Xukuru case, while at the same time putting Teófilo's expert testimony in check.Thus, an unusual 'battle of experts' (Rosen 2020, 126;Rosen 1977, 564) took place on the Inter-American level, uncovering the dynamic roles of cultural anthropologists in creating and shaping the evidence for international territorial claims.
Through the analysis of legal sources and literature review, including ethnographical works, this paper addresses the issue of anthropology's role regarding expert evidence in the transnational Xukuru land claims.It articulates the Brazilian and Inter-American legal framework on expert evidence and Indigenous land rights with the literature on 'anthropological expertise' (Foblets et al. 2020, 5;Foblets 2016, 231;Rosen 1977, 555) and 'cultural expertise' (Good 2008, 547;Holden 2022, 671-675), which includes the branches of forensic social anthropology and expert social anthropology (Rose 2022, 36).This analysis is positioned at the intersection between law and social or cultural anthropology (hereinafter anthropology) and underscores the evolving challenges of expert witnessing in legal administrative procedures on the national and international levels.
In terms of structure, this paper proceeds in the following way.After this introduction, the second part familiarizes the reader with the Brazilian framework on Indigenous land rights, highlighting the primary role of anthropological expertise in the administrative procedure.Next, the third part examines the complex challenges of anthropologybased expertise in the Xukuru case, which are considered in light of Indigenous land claims on Brazil's Northeast coast.Then, the fourth part examines the role of anthropological expertise on the Inter-American level in view of the Xukuru case.Likewise, it grasps the related socio-anthropological expert witnessing (hereinafter anthropological expert witnessing), its influence on the final judgment, and contribution to the international adjudication of human rights cases.Lastly, the final remarks highlight this paper's main contributions and contrast the multiple roles of anthropological expert evidence in domestic and international settings.

Brazil's Legal Framework on Indigenous Land Rights and the Role of Socio-Anthropological Expert Evidence
Brazil's normative framework on Indigenous land rights is sophisticated and comprehensive. 6Dating back to 1611, its progressive development over centuries (Cunha 2018, 359-402;Mendes Junior 2018, 407-461;Terena 2015, 66-81) has resulted in a substantive body of law, whose application and implementation require expert knowledge.The interpretation of relevant ordinary laws must follow constitutional and human rights provisions, including key treaties related to the rights of Indigenous Peoples, such as the International Covenants and the International Labour Organization Convention 169 Concerning Indigenous and Tribal Peoples in Independent Countries (hereinafter C169).
Also, the hermeneutic task in cases concerning Indigenous land rights is surrounded by a context of divergent political interests that are intertwined with unequal power relations, which was recently demonstrated in a landmark decision regarding the interpretation of the timeframe (marco temporal) concerning Indigenous land titles, established in previous case law (Supreme Federal Court 2009).At issue was whether only territories disputed or occupied by Indigenous peoples on the date the Constitution was promulgated (October 5, 1988) could be kept or demarcated.Such an argument, if accepted by the judiciary, would represent a major setback for the rights of Indigenous peoples, particularly because it would leave in an unfair situation and without legal protection Indigenous peoples who were forcibly displaced from their traditional lands before 1988 during the military dictatorship (Brazil 2014, 203).
After a lengthy trial, Brazil's Supreme Federal Court ruled against establishing the 1988 timeframe for Indigenous lands (Supreme Federal Court 2023a).In doing so, it promoted Inter-American human rights standards and the rights of Indigenous peoples and affirmed that the demarcation is a declaratory procedure, through which original territorial rights associated with the use of traditionally occupied lands by Indigenous peoples are recognized (Supreme Federal Court 2023b). 7In other words, the demarcation does not create rights.Rather, it recognizes 'original rights' in the sense that the rights of Indigenous peoples existed before the Brazilian state was constitutionally established, and even before Portuguese colonization.Legal scholarship clarifies that these rights are equivalent to 'natural rights' (Silva 2018, 21).
The Supreme Federal Court's judgment echoes Brazil's Constitution and its sectionwith an outdated nomenclature of -'On the Indians'. 8Article 231 of the Brazilian Constitution, the section's critical provision, is an achievement of Xikão Xukuru and other Indigenous representatives as a direct result of their political engagement with the constitutional assembly (Krenak 2012, 122-124;Pataxó 2021, 82-84).The Brazilian Constitution recognizes Indigenous peoples as first inhabitants and therefore, entitled to special rights concerning various aspects, such as customs and territory, within the limits of the state (i.e.without sovereignty). 9As a way to exercise their collective legal capacity, the Indigenous movement has created associations with collective legal personalities.The Articulation of Indigenous Peoples of Brazil (Articulação dos Povos Indígenas do Brasil) was recently recognized as having legal standing before the Supreme Federal Court (Supreme Federal Court 2020, 2).
In contrast to many legal systems worldwide, especially European ones, Brazilian law pronounces the differences between individual and Indigenous property that is under the scope of a collective right. 10First, Indigenous land rights are regulated by a legal regime based on the Constitution, while individual property is governed by civil law.Second, Indigenous territories are subject to more restrictions than individual property.This last one entails rights related to jus utendi, jus fruendi, and jus disponendi (African Court on Human and Peoples ' Rights 2017, para. 124;Lenzerini 2012, 27).Third, the Constitution recognizes Indigenous territories as inalienable and nontransferable whose ownership belongs to the Union whereas private properties belong to the individual or corporate owners. 11Therefore, Indigenous peoples may not lease, sell, or donate their lands to anyone.
It is remarkable that Indigenous lands in Brazil have a comprehensive legal protection through a unique framework.However, such protection implies restrictions for Indigenous peoples regarding their land rights, which have positive and negative aspects.For instance, Indigenous lands are not assets that can be traded on the economic market because Indigenous peoples have only jus utendi and jus fruendi rights.In addition, Indigenous leaders complain that the Brazilian land regime is inherently racist, as expressed by the eminent Indigenous leader Ailton Krenak: In Brazil, we have naturalized the colonial idea of having a part of our people that was born to live segregated.Is the seed of racial violence against Indigenous peoples not reinforced by the historical strategy of the Brazilian state to keep Indigenous peoples segregated in territories (for example, through settlements) that are configured as spaces of exclusion rather than spaces of inclusion in Brazilian life?[ … ].Indigenous territories are now surrounded by agribusiness and under intense surveillance by mining companies, which want to invade our living spaces, thus perpetuating a relationship of inequality that is the affirmation of this racism against the original peoples here in this part of the world.(Milanez et al. 2019, 11) Despite the negative aspects, the Brazilian framework on Indigenous land rights is considered a powerful legal tool among lawyers, legal practitioners, and experts (Dallari 1991, 317;Santilli 2007, 79-85;Souza Filho 2021, 314;Terena 2015, 81-82).'Progressive' was the description of Brazil's constitutional provisions on the rights of Indigenous peoples by James Anaya, former United Nations Rapporteur on the Rights of Indigenous Peoples, who, after a country visit, praised the 'advanced methodology' used to demarcate and register Indigenous lands (Human Rights Council 2009, paras 36-45).
Delimitation, demarcation, and titling are standard legal administrative procedures in Brazil and several other civil law countries, which are necessary to protect Indigenous territories.The official geographical limits of Indigenous lands are established during those procedures whose aim is to ensure a piece of land for the subsistence and development of Indigenous peoples, registered before both the notary and the Federal Heritage Secretariat, according to Article 6 of Decree No. 1.775/96.The National Indian Foundation (hereinafter NIF)the main state agency responsible for promoting and protecting Indigenous people's rights and interestsis responsible for protecting Indigenous peoples in demarcated lands or lands submitted to an ongoing demarcation procedure (Souza Filho 2013, 25).It oversees the whole administrative process, in which the Indigenous people concerned through their traditional representatives must participate (Article 2, paragraph 3 of Decree No. 1.775/96, and Article 2 of Guideline No. 14/96 of the Ministry of Justice). 12 Anthropology plays a critical role in delimitation, demarcation, and titling.An anthropological expert report (estudo antropológico de identificação) must substantiate the procedure, according to Article 2 of Decree No. 1.775/96.This report must be complemented by an interdisciplinary expert report (relatório circunstanciado de identificação e delimitação de terras indígenas) elaborated by a team (preferably, NIF staff members) under the supervision of an anthropologist who must have a 'recognized qualification.'The NIF has the discretion to choose the anthropologist and to create the demarcation team.It has recently opened five new teams, most of which were composed of individuals qualified as Brazilian specialized indigenists.At the time of writing (November 2023), Guideline No. 14/96 of the Ministry of Justice sets the framework for the interdisciplinary expert report.Likewise, it must be divided into (at least) seven sections with specific requirements: general information; permanent habitat; economic activities; environment; physical and cultural reproduction; land ownership; conclusion, including the limits of the Indigenous territory.
Against this background, this analysis notes that territorial identification does not follow a bottom-up approach but rather a top-down one: the form fields must be filled in.Consequently, anthropologists must conduct the challenging task of transforming conceptual tools of anthropological analysis into objective answers for the report.In doing so, they deal with controversies widely explored in the literature, such as the 'taken-for-granted divide between anthropology and law' (Foblets 2016, 233).Put differently, they face many dilemmas that include what to do when the reality observed through an anthropological lens does not match the legally established requirements.For example: How to classify in the report cultivated areas that play multiple roles in the life of the group, namely, subsistence and physical reproduction of the community (Barretto Filho 2005, 127)?How to legally translate the Indigenous concept of -koha found among the Zo'é people in Brazil, which does not correspond to the report's legal category of 'permanent habitat' (Gallois 2004, 38)?
Brazilian-based anthropologists have progressively developed powerful tools that engage with the local needs of expert evidence production (Lima and Beltrão 2015, 7-16;Valle 2015, 324-330).The Protocol of Brasilia ( 2015) and the Charta of Ponta das Canas (2001) are highlights among them.Developed by BAA, given a cooperation agreement with the Brazilian Federal Prosecution Office, this Charta is a reference document that contains practical guidelines for elaborating anthropological expert reports (i.e.laudo, parecer ou relatório) (Associação Brasileira de Antropologia 2001, 5).It is not legally binding and provides rather 'recommendations' concerning the anthropologist's decision-making process of accepting a case, the comprehension of anthropological discourse in legal documents, and some key points on anthropological expert reports regarding ethnic identification, traditional lands, and socio-environmental impact (Associação Brasileira de Antropologia 2001, 10-14).
To better understand the anthropological practice of report-making in Brazil and its related challenges, the following section delves into the Xukuru land recognition process.

Snapshot One: Identifying and Delimitating Xukuru's Territory
'This whole situation is dubious and complicated' 13 (Fialho 1992, 84) was the description of the Xukuru's demarcation context by Vânia Fialho, the anthropologist responsible for the team that elaborated the official interdisciplinary expert report on the Xukuru land. 14Two agronomists and one technical assistantan illustratorwere members of the group, all of them working for governmental agencies (namely, NIF, National Institute for Colonization and Agrarian Reform, and State Foundation for Agrarian Planning in Pernambuco State).The legal framework in force at that time was slightly different from the current one, explained in the previous section, since it excluded the anthropological expert report.Instead, it required a multi-institutional and interdisciplinary effort to produce one comprehensive expert report that included a territorial map, which turned out to be very challenging and one of the reasons behind Fialho's statement quoted above.
In 1989, Xukuru's territory was fragmented.In consultation with Xukuru's leaders, Fialho and the technical assistant identified 296 incidental properties to the Xukuru's land (Fialho 1992, 73-74).This information was crucial to understanding Xukuru's geographical context because it demonstrated the non-Indigenous occupation that needed to be relocated.However, according to the literature (Fialho 1992, 73-74), one of the team members, the agronomist, refused to include it in the territorial map for ideological and methodological reasons.Likewise, he disagreed with the criteria used by Fialho to define the territorial boundaries because they did not correspond to the regular criteria used by non-indigenous communities.Additionally, he stated that due to the short time allotted for fieldwork and the small size of the incidental properties, he could not adequately include them in the territorial map.According to him, a small-scale map could only be produced over a longer period of time.Thus, the agronomist's individual report on land ownership excluded the 296 properties.
Fialho's ethnographic remarks on the political tensions and the ideological controversies among the team members should be taken into account in order to understand the agronomist's approach regarding the elaboration of the territorial map.However, to fully understand it, the hurdles of interdisciplinary teamwork in producing expert reports must be considered.Interdisciplinarity is helpful for better framing Indigenous territorial claims due to the nature of 'Indigenous lands', which embodies notions of multiple epistemologies (Pereira 2023, 41) and various disciplines, including law, anthropology, and philosophy.For instance, Brazilian anthropological literature (Gallois 2004, 39) distinguishes between 'Indigenous lands' as a legal-political process conducted by the state and 'Indigenous territories' as a relationship between an Indigenous group and its territorial base.Importantly, Gallois notes that these concepts are absent among selected Indigenous peoples who do not have in their social system the idea of geographical boundaries.In addition, she explains that other groups have incorporated such concepts into their vocabulary and practices to engage with the state, which exposes the lingering effects of colonialism that shapes Indigenous languages and ways of life.
The co-work of multiple fields does not constantly develop harmoniously.It is usually quite the opposite.Every field has its epistemology, which produces a specific type of knowledge and expresses it according to its principles through a discipline-based nomenclature.Likewise, professionals from different backgrounds who must work together are especially vulnerable to misunderstandings regarding technical issues, disputes regarding methodologies to be applied, and communication obstacles.
The Brazilian legislation on Indigenous land rights evolved and recognized this necessity regarding the different timeframes of expert reports in interdisciplinary teams, as pointed out by the agronomist.Currently, it stipulates in Decree No. 1.775/96 a different methodology for these reports compared to the one in the Xukuru case, namely, a sequence of the anthropological report followed by studies on land ownership, which enables more consistency in setting territorial boundaries.Such methodology allows the different disciplines to work with a little more flexibility in terms of time.
Moreover, other challenges behind the elaboration of the anthropological expert report in this case were Colonialism and interethnic conflicts that, if examined concurrently, underscore the high legal-political value of expert evidence.Denying or invisiblizing the existence of specific subjects to exercise control over their geographical habitat is one of the main features of Colonialism (Anaya 2004, 29;Anghie 2006, 742-746), which is understood in this paper as a political, economic, theoretical, and ideological system of domination.Colonial powers that emerged in the fifteenth century developed this system whose effects continue until the present days (Santos 2017, 246-247), as elucidated by the Indigenous leader Ailton Krenak 15 : The only group who still consider they need to hold on to this earth are those that have been half-forgotten on the edges of the planet, on the banks of rivers, on the shores of oceans, in Africa, Asia, or Latin America.They are a sub-humankind: traditional communities, Indians, Afro-descendants, and aboriginal peoples.Thus, there is a humankind that is part of a selected circle and does not accept new members; And there is a more rustic and organic layer, a sub-humankind, stuck to the earth.I do not feel part of humankind.I feel excluded from it.(Krenak 2020, 82-83) A paradigmatic application of Colonialism is the legal doctrine of terra nullius, which can be translated from Latin as 'empty territory.'It was used by colonial powers to pierce a legal veil in the occupation of territories, including Indigenous ones, across the world (Gilbert 2006, 26).Colonial powers grabbed Indigenous lands under the justification that Indigenous peoples could not exercise proper territorial sovereignty.This doctrine was not only applied in the international arena by European powers but also within national contexts after the official end of colonization, for instance, in Australia (Chalmers 2020, 464) and Canada (Borrows 2015, 702).
Examining the Xukuru case underscores an implicit application of the terra nullius doctrine on Brazilian soil, which was not legally sound (J. A. da Silva 2018, 33-34).In the past, Indigenous peoples close to Brazil's Northeast coast were commonly believed to have disappeared.Anthropological scholarship explains that due to the absence of 'strong cultural contrasts' between Indigenous, non-Indigenous, and interethnic groups living on the Brazilian Northeast coast, it was difficult to identify ethnic communities.The famous Darcy Ribeiro and other anthropologists believed that Indigenous peoples had disappeared through assimilation or integration into the larger society.Indeed, they were legally declared as extinguished in the early nineteenth century (Oliveira 2007, 2-5;Oliveira 2011a, 653-654;Fialho 1992, 85;Silva 2017b, 41-43).
Likewise, especially after the enactment of the 1850 Law on Lands, 16 the Xukuru territory was progressively occupied by the local elite (i.e.mill owners, livestock farmers, and large landowners).According to their own statements (Silva 2017b, 149-155), members of the Xukuru people were forced to move to other regions or to stay in very poor conditions.Under political and physical threat by the local elite, they decided to hide their identity as Indigenous that legally entitled them to land titles, putting their lives at risk.They started to self-identify as 'caboclos', a category that is similar to mestizos: persons with a mixed racial background who were deprived of their lands (Silva 2017b, 41).The 'caboclos' and the 'coloured' (Clifford 1986, 284) may be contrasted to some extent because both notions are interwoven with issues of race and ethnicity.In this regard, Silva's fabulous work makes a crucial remark 17 : The so-called caboclos or descendants of Indigenous peoples close to Brazil's Northeast coast were regarded from the perspective of cultural loss.For this reason, they were long forgotten.In anthropological studies, they were marginal populations, dispossessed, considered to be completely acculturated, when placed on an evolutionary scale, compared to the Indigenous groups of Northern Brazil, who were the bearers of a legitimate and supposedly original cultural purity.Therefore, the historical processes experienced by these populations were neglected.(Silva 2017b, 94-95) Anthropologyand anthropological expert reportsregarding Indigenous peoples in the Brazilian Amazon region concerned the maintenance of Indigenous territories threatened by non-Indigenous invasion movements (Oliveira 1998, 53).Conversely, in the Northeast region, the issue pertained to reestablishing Indigenous lands, which had been illegally occupied for decades by non-Indigenous persons.Those persons often belonged to the local elite who claimed that 'a bunch of poor persons in 'Indian' costumes wanted to usurper their rightful properties' (Valle 2004, 254).'Indigenous peoples in the Brazilian Northeast region update the dilemmas examined concerning the Ndendeuli of Africa and the Mashpee of North America' (Oliveira 1994, 126), 18 explained mainstream scholarship.Indeed, this situation in Brazil connects with more recent discussions on 'transformative survival' (Clifford 2013, 18) that are observed in the global indigenous movement, as it concerns resistance and transgression.
A unique toolkit is needed for anthropological researchand, of course, for producing anthropological expert reportson Indigenous peoples living in Brazil's Northeast region due to colonialism-linked specificities.This analysis situates Fialho's work among the leading pieces under the so-called 'ethnology of losses and cultural absences' (Oliveira 2014, 25;Oliveira 1998, 53) that in recent studies has been combined with ethnohistory.It grasps how and why the Xukuru people and several other groups remained together as a society, 19 despite being officially declared extinguished and their lands vacant (Fialho 1992, 30-54).Likewise, interethnic conflicts attached to land ownership were critical for identifying 'Indigenousness' or 'Indigeneity' (indianidade).They constituted the bedrock of the Xukuru society, as explained in anthropological scholarship 20 : [ …] in the face of conflict, of the presence of the other with expectations around him/her, signs are elaborated along with a whole symbolic structure capable of adapting the community in question to standards externally imposed on it.Indigenousness (indianidade), as a social process resulting from a social relationship, does not come from the mental conception of only one of the parties involved.Rather, it is the product of this conflict of confrontation.(Fialho 1992, 137) According to this paper, 'Othering'as a process of creating or highlighting differencesin connection with a geographical area, embedded in the unique notion of the 'territorialization process' (Oliveira 2014, 19;Oliveira 1998, 55), was fundamental in Fialho's anthropological work.More recent scholarship has built on the concept of 'territorialization' and added to the toolkit of identification of Indigenous peoples in Northeast Brazil the consideration of the role of symbolic collective practices, as, for instance, 'planting' deceased community members (as explained above in the introduction) or conducting the religious ritual of Toré (Oliveira 2007, 16).
The anthropological expert report for the delimitation of the Xukuru land contributed significantly to the empowerment of Indigenous peoples in the Brazilian Northeast region.Its nature as an official document was essential to tackle the ongoing effects of Colonialism, namely the historical dispossession of the Xukuru people.Other anthropological reports followed the Xukuru one, and they helped to progressively establish evidence for the undeniable: Indigenous peoples have always lived in Northeast Brazil, and no vacant territory exists.Such conclusions may support many lawsuits concerning Indigenous territorial claims and, thus, have extended implications in legal practice, especially due to the increasing legal disputes of Indigenous demarcation procedures in Brazil (Batista and Guetta 2018, 304-306).
Finally, Fialho's expert report also contributed to the external process of legally recognizing the Xukuru people.Drawing upon the contrasts among the people living in the area, it accentuated the geographical boundaries before an entity (Fialho 1992, 144)the state, whose importance both Indigenous and non-Indigenous peoples recognize.Unfortunately, in the case at hand, fostering legal recognition implied enhancing inter-ethnic conflicts, ultimately resulting in the adjudication before an international human rights court.Conflict is thus a two-sided coin with positive and negative effects in the Xukuru case, whose international adjudication is the next section's subject.

Snapshot Two: Anthropologists and Expert Evidence in the Inter-American Context
The anthropological expert evidence presented in the Xukuru complaint was the oral and written declarations of Christian Teófilo, an anthropologist with international credentials, as a member of the BAA and the Canadian Society of Anthropology, and a professor at a leading university in Brazil. 21Interestingly, he was not the only anthropologist present at the court hearing.Professor Dr. Vânia Fialho, who wrote the expert report discussed in the previous section, was in the courtroom.For reasons discussed below, she was dismissed as an expert witness by the IACtHR on the basis of prehearing objections by the state (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.54:00-55:00), which was a significant limitation on the evidence presented by the legal representatives of the Xukuru people and had negative effects on the reparations awarded.
Nevertheless, Fialho's participation in the trial was allowed as a representative of the victims, which was critical during Teófilo's oral expert testimony. 22She cross-examined her colleague (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.55:00-59:00), thus making up an unusual 'battle of experts' (Rosen 2020, 126;Rosen 1977, 564) on the Inter-American level.Unusual because she could neither present herself as an expert nor directly contradict the information presented by Teófilo, as this would risk objections from the state.In order to overcome this obstacle, she raised questions that were critical of the content and methodology of Teófilo's expert report (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.55:00-55:43), while at the same time indicating her role as an expert in the field.
More interesting, though, is that the IACtHR's judgment on the merits does not refer to anthropological expert evidence, which is peculiar, an uncommon pattern in the Inter-American case law.This absence might indicate that anthropological expertise played a minor role in the judgment at hand.However, a deeper investigation is necessary to establish if this was the case and the reasons behind it.Through such examination, constraints hindering the dialogue between law and anthropology can be found and sorted out to enable the fruitful interchange between anthropological knowledge and lawmaking.
An ideal starting point for exploring this issue is the pre-trial stage, which is usually overlooked in the scholarship on anthropological expert evidence.This analysis observes that anthropological expert witnessing in mainstream literature focuses on the substance of testimonies in common law countries (Good 2008;Rosen 1977), perhaps because the pre-trial stage is less important in shaping the evidence due to the broad judicial discretion available in these jurisdictions.Nevertheless, in civil law-based or international legal systems, including the Inter-American Human Rights System (hereinafter IAHRS), the pre-trial phase is a deciding moment to ascertain expert qualifications and frame the substance of declarations and testimonies.This stage answers vital questions, such as who will speak, in what capacity, and about what, all of them of procedural nature.Victims' representatives may find it challenging to address them in their written pleadings, as answering these questions require a special knowledge of how to litigate in the IAHRS.The very definition of expert evidence is shaped in the pre-trial, which influences the role it will play in the decision-making, outcome, and redress measures.
The IAHRS works on the basis of party-appointed expert witnesses (hereinafter experts) who are appointed and confirmed in specific procedural moments, in accordance with Articles 46, 47 and 48 of the 2009 IACtHR's rules of procedure that are still in force at the time of writing.As explained elsewhere (Monteiro de Matos 2023, 758-759), the reason behind the strict procedural stages for indicating declarants relates to the principle of due process of law that is interwoven with the parties' right to raise objections against and even refuse an expert proposed by the opposing party (Articles 47 and 48 of the 2009 IACtHR's rules of procedure).
In the present case, the state objected to the expert presented by the Inter-American Commission on Human Rights (hereinafter IACHR), the former United Nations Special Rapporteur on the Rights of Indigenous Peoples Victoria Tauli-Corpuz, on the grounds of untimely appointment, which the judges rightly rejected (Inter-American Court of Human Rights 2018, paras 7-8).It is highly likely that the state raised a similar objection to Fialho's expert testimony, which led to her dismissal as an expert witness.There is no specific information on this matter in the publicly available information on the proceedings, but the likelihood is based on the applicable procedural rules.The IACtHR noted in its decision that the representatives of the victims did not file their initial written pleadings, which is the appropriate procedural moment for the appointment of experts.
The state indicated its expert in the Xukuru case without objection by the IACHR or the victims and their representatives.In accordance with the resolution of the IACtHR's acting president of January 31, 2017 (hereinafter the resolution), the state framed Teófilo's testimony through a dual perspective, namely legal and socio-anthropological, something not uncommon, for which there are precedents in the Inter-American case law.For instance, the testimony of Professor Rodolfo Stavenhagen in the Awas Tingni case. 23According to this resolution, Teófilo was bound to declare about the Brazilian legal framework on Indigenous land rights, the procedure regarding the demarcation of lands, the relationship between Indigenous peoples and their occupied lands in Brazil, and the relevance of cultural aspects for the territory.
Against this background, this paper problematizes the question of 'Who is the expert?' Teófilo's qualifications met the legal requirements established in the IACtHR's rules of procedures, which are easily satisfied with proof of knowledge or practical experience. 24 Conversely, these rules fail to meet a main requirement established for 'anthropological expertise,' namely, doing ethnographic fieldwork with the Indigenous peoples who are relevant to the expert report (Fialho 2015, 314;Loperena 2020, 603;Rose 2022, 32).Being close to the research subjects is the hallmark of the ethnographic method (Malinowski 1984, 17-22), which differentiates 'anthropological experts' from 'cultural experts' (Holden 2019, 673-674).This last type of expertise encompasses other disciplines besides anthropology.Similar mismatches regarding the official and academic requirements for being an expert also occur in other countries.For instance, Hale described his anthropological expert witnessing concerning a case on genocide, in which a leading anthropologist on this topic was precluded from declaring as an expert due to his 'firsthand observation of the genocidal acts' (Hale 2020, 622) that implied an absence of neutrality.
More important, however, is that this Inter-American mismatch between legal and scholarly requirements raises questions about the necessity of the ethnographic method for elaborating expert reports and testimonies.Anthropological scholarship has extensively debated this issue, which acquires new dimensions here in view of the international feature of the Xukuru case.International law works very differently than national legal proceedings, especially regarding the standard of proof.Due to that, it is arguable that international decision-making does not require evidence with highly accurate information regarding Indigenous lands that may only be obtained through fieldworkas domestic courts do.In what follows, this research explores whether this hypothesis can be sustained in view of the Xukuru case.
Prima facie ethnographic work was unimportant for elaborating the expert evidence since, according to the legal proceedings, Teófilo's scope of testimony was broad and concerned mostly the Brazilian legal context of Indigenous land rights.Put differently, his declaration was not specific to the Xukuru case, which was a limitation well understood by the IACtHR's judges, as observed in the public hearing (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.60:00).Indeed, Teófilo was very professional and careful in explaining during his 'narrative testimony' (Rosen 1977, 572) that his expert witnessing was based on the available scholarly literature because he did not conduct fieldwork among the Xukuru people (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.12:30-12:40).Indeed, he enumerated in his expert report the sources for his testimony and indicated several legal documents among them, including key international instruments on the rights of Indigenous peoples, such as the C169 and the United Nations Declaration on the Rights of Indigenous Peoples (Silva 2017a, 3-4).In his oral explanation, he quoted Fialho's ethnographic work and emphasized his methodological approach several times, thus, communicating clearly to all the parties involved the intrinsic limits of anthropological expert witnessing without first-hand collected data.
As an additional remark, this analysis notes a significant shortcoming in Teófilo's testimony that refers to his conclusion that the amount of time spent in Xukuru's land demarcation process was 'reasonable' (Silva 2017a, 6).This conclusion reflects his overall approach in the written report that devotes 20 pages (out of 64) to examining Brazil's legal framework on Indigenous land rights (Silva 2017a, 5-25).The critical point is that this notion (i.e.'reasonable') is not an anthropological one.Instead, the legal concept of 'reasonable time' emerges from the principle of the due process of law in administrative law.Therefore, it is compelling to indicate the methodological inadequacy in the sense that Teófilo went beyond the limits of his expertise.Experts should use concepts within their field of expertise.Otherwise, their testimonies may be regarded as inaccurate, thus, negatively influencing the evidence-weighing process. 25Indeed, Teófilo's statements and expert report (Silva 2017a, 28) aligned with many of the arguments presented by the state, which qualifies the expert evidence as a result of 'non-activist research' (Hale 2006, 99), and resulted in open criticism by Indigenous peoples and their representative institutions in Brazil (Oliveira, Maria Neves, and Fialho 2022, 426).
During the cross-examination by the IACtHR's judges, Teófilo restated: 'I am not an expert on the Xukuru people' (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.83:00).This statement reveals his engagement with courtroom dynamics, and, especially, the nature of the follow-up questions asked by the decision-makers that related to second part of Teófilo's expert report (Silva 2017a, 28-56), in which he responded to questions raised by the opposing parties, according to Article 50.5 of the 2009 IACtHR's rules of procedure.Remarkably, the judges inquired Teófilo several times about the nature and extension of the presence of non-Indigenous persons in the Xukuru land and its ongoing effects on the life of the Xukuru people.
Given the complaint, the judges' behavior was expected since these issues were at the heart of the alleged human rights violation.The Inter-American case law on Indigenous land rights spans more than twenty years and includes similar cases about non-Indigenous people's presence in claimed Indigenous lands in the judgments concerning Paraguay (Inter-American Court of Human Rights 2005; Inter-American Court of Human Rights 2006; Inter-American Court of Human Rights 2010) and Honduras (Inter-American Court of Human Rights 2015a; Inter-American Court of Human Rights 2015b), for instance.Perhaps due to the unfamiliarity with the Brazilian context combined with the general information presented in Teófilo's oral testimony, the judges were still puzzled by the case at hand.They wanted in-depth information on the situation regarding the Xukuru people and seemed unsatisfied with Teófilo's answers.As a result, they asked for additional information from the parties regarding the number of non-Indigenous persons living in the Xukuru territory to be included in their final written pleadings (Inter-American Court of Human Rights 2018, para.51).
This paper observes that the judges went beyond the pre-determined scope of Teófilo's testimony in the cross-examination, a dynamic that was legal under the Inter-American procedural rules but perhaps unexpected for the expert.Beyond his expert field, Teófilo provided limited and inaccurate information, as he admitted before the IACtHR (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.82:00).He confessed not recalling the extension of Xukuru's claimed landsa fundamental aspect of the caseand was unable to respond to the judges' questions thoroughly.Likewise, this analysis notes that Teófilo's limited knowledge regarding the Xukuru people (i.e. based on secondary sources) was not adequate to support the decision-making and constrained the role of anthropological expert evidence in the present case.Given the merits of the judgment, such a conclusion becomes even more evident.
On the Inter-American level, the IACtHR evaluates the evidence submitted in light of many principles, among which the 'sana crítica' is critical.Translated as 'sound judicial discretion,' this principle reflects how the standard law system weighs the evidence (Paúl 2018, 9).It demands a logical and comprehensive analysis of the evidence presented that facilitates the external assessment of the role of proof in a given case: If the reader wishes to know the evidence that supports a particular finding, he or she must read the section of proven facts, where the IACtHR will include in a footnote all the evidence that contributed to its finding, without mentioning the different value that it grants to each means of evidence.(Paúl 2018, 10) Following a doctrinal approach according to the Inter-American principle of sound judicial discretion, the fact that the IACtHR's judgment in the case at hand does not mention Teófilo's expert evidence indicates the attribution of low weight to it.The reduced role of anthropology-based evidence in this case may also be related to a technical aspect.The written anthropological expert evidence was submitted in Portuguese, which is not a common language among the judges.One of them admitted not being able to read the anthropological expert report due to language barriers (Caso Pueblo Indígena Xucuru y Sus Miembros vs. Brasil 2017, pt.68:00).This issue could have been avoided with adequate technical language support from the state or by hiring a professional with more experience on the Inter-American level, who would likely be aware of such language obstacle.
Finally, to conclude the assessment regarding the role of anthropological evidence in the present case, it is crucial to look at the 'secondary effects of expert testimony' (Rosen 2020, 136).This notion is significant for analyzing the Inter-American adjudication system that allows the evidence produced for one case to be carried on to another, which implies taking evidence from one situated context to a different one, something uncommon in anthropological scholarship that is based on situated knowledge.The IACtHR has usually been explicit when incorporating proof from a previous case to another, which is a regular practice in different cases involving the same country.However, the Xukuru case indicates that such 'evidence loaning' may work implicitly and even in complaints involving different communities and countries.
The Xukuru and the Garífuna cases (Inter-American Court of Human Rights 2015a; Inter-American Court of Human Rights 2015b) have similarities, such as being decided by almost the same judges and sharing factual patterns.Indeed, both peoples were threatened by the presence of non-Indigenous persons in their lands whose dangerous and illegal character was elucidated in the expert evidence concerning the Garífuna cases submitted by the anthropologist Christopher Loperena and the lawyer José Aywlin.From a legal perspective, Aywlin explained the limited exercise of Indigenous land rights if an Indigenous territory is fragmented in accordance with a reliable legal source, namely the official interpretation of the C169 (Caso Comunidad Garífuna Triunfo de La Cruz y Sus Miembros vs. Honduras 2014, pt.9:00-10:00).In addition, through an anthropological lens, Loperena explained in his expert testimony the notion of 'cultural loss' (Loperena 2020, 601) associated with the change of ancestral modes of food production due to the presence of non-Indigenous individuals in the Garífuna land.
Likewise, the IACtHR's judgment on the Garífuna case is paradigmatic for upholding the state's obligation regarding sanitation measures under the threshold of Article 21 of the ACHR (Monteiro de Matos 2021, 10:245), which was also recognized and further elaborated in the Xukuru case.The judgment at hand refers several times to the decisions in the Garífuna cases, suggesting an ongoing dialogue between them.This paper notes that the link between the two cases demonstrates case law consistency, and beyond that, it indicates indirect effects of expert testimony, constituting what can be denominated a cross-fertilization of anthropological evidence under the Inter-American law, a category that needs to be further explored in the scholarship.

Final Remarks
Conceiving, writing, submitting, and interpreting anthropological expert evidence are common activities in the life of courts and beyond.As this research demonstrates in light of Indigenous land claims in Abya Yala, this type of evidence may relate to territorial disputes, which are interwoven with topical debates concerning the ongoing effects of terra nullius and Colonialism.The multilevel analysis of the Xukuru case exposes the new challenges to the interdisciplinary field constituted by anthropology and law, which have developed with the emergence of regional human rights systems and courts.As mainstream scholarship explains, anthropology has become a foundational part of the continuing evolution of human rights (Goodale 2017, 96).
This paper underscores the multiple roles played by anthropology and anthropological expert evidence nationally (in Brazil) and internationally (on the IAHRS).These roles are directly related to the settings in which expert evidence is produced.Expert witnessing on the IAHRS is oral and written, in a more flexible model (i.e. a combination of 'narrative testimony' and cross-examination), less attached to the case's specific circumstances, and party-driven.Conversely, expert evidence for legal-administrative national procedures is written in a legally pre-defined format, answering requirements, based on fieldwork involving land tenure disputes.These two formats of anthropological expert evidence resemble the model concerning 'forensic and expert social anthropology' (Rose 2022, 34-35), which engages with critical debates in anthropological scholarship by suggesting a continuum between the multiple potential roles of anthropologists in legal proceedings.Due to the specificities of each level (national and international), this analysis concludes that anthropologists acting as experts need different sets of skills, which can be developed through special training.
Finally, it is worth mentioning that anthropological expertise is critical in protecting the rights of Indigenous peoples and traditional communities.Anthropological expert evidence may not decide lawsuits by itself, but legal practice shows it is a milestone for decisionmaking and legal reasoning (Dallari 1994, 114).Mrs Deborah Duprat, eminent Brazilian attorney, who was for many years in charge of the Brazilian Office for protecting Indigenous peoples, says that: 'Anthropological intervention is a critical step in the process of Indigenous peoples' self-determination' (Duprat 2015, 17). 26According to Article 3 of the United Nations Declaration on the Rights of Indigenous Peoples, by virtue of the right to self-determination, Indigenous peoples are free to determine their political status and pursue their economic, social, and cultural development.Self-determination as a right needs the law to guarantee, based on grounded anthropological knowledge, that Indigenous peoples have the (tangible and intangible) conditions to be and to 'lift the sky' 27 : My people, as well as other relatives, have this tradition of lifting the sky.When it gets too close to the earth, a type of humanity feels this pressure due to its cultural expressions.[ …].It is necessary to dance and sing to lift it so that changes concerning the health of the earth and all beings take place in this passage.When we do the taru andé, this ritual, it is the communion with the web of life that gives us power.(Krenak 2020, 45-46) Notes 1. Information available at: https://osprimeirosbrasileiros.mn.ufrj.br/en/contemporary-world/xucuru/ (last accessed: 12/12/2023).For a subjective account by the Xukuru people on Chief Xikão's life, see the documentary: https://www.youtube.com/watch?v=-tbVB6zCl6w (last accessed: 12/12/2023).2. The literature is not uniform with respect to the orthography of the name Xukuru, which can be found under several names, such as 'Xacuru', 'Xucuru' or 'Sucuru'.This paper opted for writing it with 'k', following the criteria of self-identification and mainstream scholarship.3. The Brazilian Superior Court of Justice has recently ruled that the judgment against Chief Marcos Xukuru contained several errors and should therefore be considered null and void.The Court explained, for instance, that the witnesses' testimonies should not have been considered as evidence because the people called as witnesses in the legal proceedings had a vested interest in the criminal conviction of Chief Marcos Xukuru.4. Free translation by the author from the original in Portuguese to English. 5. Information found on the Brazilian researchers' database: http://lattes.cnpq.br/3919969920731350 (last accessed 12/12/2023).6.This paper uses the concepts of Indigenous lands and Indigenous territories as interchangeable, despite the differences under Brazilian law.For an elucidation of the differences, see: (Souza Filho 2013, 20-21;Supreme Federal Court 2009, 233-234).7. Currently, the indirect consequences of this judgment are still unfolding.The Brazilian Congress is considering a bill that would establish the 1988 timeframe for Indigenous lands.
8. Unfortunately, the national legal framework uses an outdated terminology for the land's right holders, naming them as 'Indians', which is a word regarded as incorrect in the field of social sciences, mainly due to its derogatory connotation.The most adequate term according to the current international law standards is 'Indigenous peoples' (International Labour Organization 1989; United Nations 2007), which is also used by many Indigenous individuals to self-identify.Administrative and legislative powers have recently started to use this wording through simple steps, such as Law 14.402 of July 8, 2022, which changed the name of the commemorative date from 'day of the Indian' to 'Indigenous peoples' day', or the presidential government of Lula da Silva (Brazil 2023) that created the Ministry of Indigenous Peoples.'Indigenous' comes from the Latin indigena and means in colloquial language someone belonging naturally to a region (Monteiro de Matos 2021, 10:1).9.The relationship between the concept of sovereignty and Indigenous peoples in Brazil has changed over time.The current Constitution contrasts with previous colonial legislation that recognized Indigenous peoples as sovereign nations (Cunha 2018, 367).Notably, selected Indigenous peoples self-identify as Indigenous nations.10.There is an absence of consensus in legal scholarship on the definition of collective or group rights.However, the mainstream definition (Wenzel 2011, para.2) places the difference between individual and group rights in the category of 'right holder'.Likewise, to be classified as a collective right, the relevant rule should entitle a group (rather than individuals) with a specific right.In light of this understanding, this paper classifies the rights of Indigenous peoples in Brazil, including land rights, as collective ones, which is clearly established by Articles 231 and 232 of the Brazilian Constitution.11.Article 231 of the Brazilian Constitution reads as it follows: Indigenous people shall have their social organization, customs, languages, creeds and traditions recognized, as well as their original rights to the lands they traditionally occupy.The Union is responsible for demarcating such lands, protecting and ensuring respect for all of their property.Paragraph 1. Lands traditionally occupied by Indians are those on which they live on a permanent basis, those used for their productive activities, those indispensable to the preservation of the environmental resources necessary for their wellbeing and for their physical and cultural reproduction, according to their habits, customs and traditions.Paragraph 2. The lands traditionally occupied by Indigenous are intended for their permanent possession and they shall have the exclusive usufruct of the riches of the land, the rivers and the lakes existing therein.Paragraph 3. Water resources, including energetic potentials, may only be exploited, and mineral riches in Indigenous land may only be prospected and mined with the authorization of the National Congress, after hearing the communities involved, and the participation in the results of such mining shall be ensured to them, as set forth by law.Paragraph 4. The lands referred to in this Article are inalienable and nontransferable and the rights thereto are not subject to statute of limitation.Paragraph 5.The removal of Indigenous groups from their lands is forbidden, except ad referendum of the National Congress, in case of a catastrophe or an epidemic which represents a risk to their population, or in the interest of the sovereignty of the country, after decision by the National Congress, it being guaranteed that, under any circumstances, the return shall be immediate as soon as the risk ceases.Paragraph 6. Acts with a view to occupation, domain and possession of the lands referred to in this Article or to the exploitation of the natural riches of the land, rivers and lakes existing therein, are null and void, producing no legal effects, except in case of relevant public interest of the Union, as provided by a supplementary law and such nullity shall not create a right to indemnity or to sue the Union, except in what concerns improvements derived from occupation in good faith, in the manner prescribed by law [ … ]. (Brazil 1988) 12. Recent practices in delimitation and demarcation procedures contrast with the passive role of Indigenous peoples that was legally established.For example, in 2014, the Munduruku people autonomously began to demarcate their lands for various reasons, including to expedite the legal-administrative procedure.Such an act exemplifies a phenomenon that is crucial to understanding the Brazilian land rights regime: multinormativity.In addition, it demonstrates the multiple uses of state law (i.e. the legal categories of delimitation and demarcation) by different actors, in different ways, thus, creating a situation of interlegality.
For a comprehensive analysis in this regard, see the master's thesis of the public prosecutor Luís Boaventura (Boaventura 2023).13.Free translation by the author from the original in Portuguese to English.14. Fialho wrote her master thesis in Anthropology based on the Xukuru case while working at the Department of Identification and Delimitation of the NIF (Fialho 1992, 1).Her master thesis, which is an ethnographic account of the Xukuru land's demarcation procedure, is one of the main sources for this section.The author did not have access to the anthropological expert report for the identification and delimitation of the Xukuru land because it is not available to the general public.15.Free translation by the author from the original in Portuguese to English.16.On the effects of the 1850 Law on Lands on Indigenous territories in Brazil, see Cunha (2018, 369-375).17.Free translation by the author from the original in Portuguese to English.18. Free translation by the author from the original in Portuguese to English.19.For other anthropological works on Indigenous peoples in Brazil's Northeast region, see Oliveira (2011b;Oliveira 2004) The term 'expert witness' refers to the person whom, possessing particular scientific, artistic, technical, or practical knowledge or experience, informs the Court about issues in connection in as much as they relate to his or her special area of knowledge or experience.
As proof expertise, experts must provide the IACtHR with their curriculum vitae.25. Similarly, see Carreira (2005, 242).26.Free translation by the author from the original in Portuguese to English.27.Free translation by the author from the original in Portuguese to English.

Acknowledgement
Special thanks to the Max Planck Society for making this research freely available to the public, thereby contributing to open science.

Disclosure Statement
No potential conflict of interest was reported by the author(s).

Funding
The author thanks the Brazilian Federal Agency for Support and Evaluation of Graduate Education (known by its Portuguese acronym CAPES, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) for its generous support of this research (grant number 88887.692557/2022-00).