Authored By: Kowsar (Layla) Abdulle
Tilburg University
Abstract
The 1970 UNESCO Convention is the leading framework against illicit trafficking of cultural property, yet its capacity to secure restitution for colonial-era takings remains limited. This article argues that the Convention’s prospective application, narrow legal definitions, and procedural safeguards render it legally unenforceable for historical injustices. Examining Dutch policy and the 2023 return of the Lombok Treasure to Indonesia reveals how states circumvent the treaty through ethical frameworks. This policy-dependent approach, however, introduces risks of inconsistency and lacks judicial enforcement. The article concludes that meaningful colonial restitution requires reforming international heritage law through a dedicated multilateral instrument, transforming ethical returns into enforceable legal rights.
Introduction
The global drive for restituting cultural heritage confiscated during colonialism constitutes not just a legal challenge, but a profound test of contemporary justice. The 1970 UNESCO Convention is seen as a first step in the dismantling of the illegal art trade, but its applicability in addressing historical wrongs remains largely contested.[1] Can a prospective treaty effectively repair past injustices rooted in colonial past? The above paper evaluates whether the 1970 UNESCO Convention has the necessary legal and ethical tools to facilitate the return of relics from the colonial period. This paper focuses on three specific failings in the Convention’s design: its 1970 cutoff date that erases colonial history, its definition of ‘illicit’ that excludes systemic colonial appropriation, and its state-centric procedures that sideline claimants.[2] The 2023 Dutch restitution of the Lombok Treasure is not just an example, but clear proof of this breakdown.[3] In creating a separate ethical policy that bypasses UNESCO, the Netherlands has effectively demonstrated the treaty’s irrelevance to the most pressing restitution cases[4]. This not only highlights a gap in the law, it demands a fundamentally new legal paradigm built for change, not just regulation.
Section 1: UNESCO 1970 Convention
The UNESCO Convention outlines several fundamental legal responsibilities for states that become signatories. According to Article 2, these states are obligated to prevent illegal trafficking, and to facilitate necessary reparations.[5] Article 3 clarifies what constitutes an illicit transfer, stating that any cultural property, import, export, or ownership transfer that contravenes the provisions set forth by the Convention is deemed illicit.[6] To oversee and regulate such transactions, Article 6 mandates the creation of an export certificate system.[7] The most notable restitution provision can be found in Article 7(b), which imposes a legal obligation to recover and return stolen cultural property, albeit under specific and restrictive conditions.[8]
One significant limitation of the Convention is articulated in Article 15, which establishes a temporal scope, indicating that the Convention’s provisions only apply after it has come into force for the relevant states.[9] For the Netherlands, this effective date is 2009.[10] Consequently, any cultural property import, export, or transfer of ownership prior to this year falls outside the legal parameters of the Convention. This temporal constraint poses a considerable challenge when addressing colonial-era acquisitions predominantly conducted from the 17th to early 20th centuries.
The Convention’s definition of ‘illicit’ is not just narrow, but structurally incapable of addressing colonial-era takings. An act is only ‘illicit’ if it violates the Convention’s own, non-retroactive provisions.[11] Any taking authorised by colonial law is excluded. This legal gap reflects 19th-century doctrines that legitimised plunder, such as Robert Phillimore’s 1854 assertion that ‘acquisitions of war belong to the State.’[12] Therefore, the treaty does not have a gap, it is built around one. Its core legal category actively filters out the very historical injustices the modern restitution movement seeks to address.
Another complication affecting restitution under this Convention involves issues surrounding good-faith purchasers.[13] This article imposes conditional limitations on restitution processes. If a current possessor acquired an object in good faith, without awareness of its stolen status, the requesting country must compensate them for its return.[14] This requirement can complicate and inflate costs associated with restitution efforts. Additionally, there exists a significant procedural burden on requesting states. They must furnish evidence demonstrating illicit exportation and prove theft occurred through proper documentation (such as inventory records) while also covering all related expenses, including collection, shipping costs, etc.[15] Thus, tasked with both proof and financial burdens often disproportionately impacts former colonies with limited resources, making historical claims increasingly difficult due to potential scarcities or losses in documentation over centuries past. Collectively, these issues create a legal environment ill-equipped to effectively tackle the historical and ethical dilemmas surrounding colonial restitution.
Section 2: Dutch implementation & policy
The Netherlands adopted UNESCO 1970 as part of its national law by amending the Cultural Heritage Preservation Act in 2009, the same year it ratified the Convention.[16] The amendments introduced export controls (section 14b) and the process for returning unlawfully removed cultural property (section 16), reflecting UNESCO 1970’s core obligations.[17] These rules help stop illegal trade and allow stolen heritage to be sent back. However, they only apply to exports or removals that happened after 2009. That means colonial-era objects taken long before then are not covered.
The Dutch government introduced the 2020 Guidelines for Colonial Collections in order to deal with the gap.[18] This policy is built on three practical steps. First, it encourages working together with countries of origin by doing joint research and museum projects instead of just handling claims.[19] Second, it uses a structured request process, where an independent Advisory Committee looks at the evidence and gives advice.[20] Third, it backs provenance research through a special consortium that helps museums investigate objects and share findings internationally.[21] The whole system runs outside the courts, relying on dialogue, committees, and shared decisions instead of legal demands.
It’s clear this policy goes far beyond what UNESCO 1970 requires. The treaty only applies to things that happened after a country joins, for the Netherlands that is 2009.[22] However, the Dutch policy looks back to the colonial era, long before that date. Furthemore, UNESCO 1970 states that good faith buyers should be compensated if something is returned, the Dutch guidelines allow unconditional return once it’s proven that an object was taken involuntarily.[23] While the treaty expects formal diplomatic claims and legal proof, the Dutch way uses research, committees, and cooperation.[24] This shows the Netherlands sees colonial restitution as a question of historical justice, not legal compliance.
In practice, the UNESCO 1970 Convention is used as a symbol of good intentions rather than a legal tool. Officials might refer to the Convention to show the Netherlands supports global heritage norms, but it is not the real reason objects are returned. The main policy is under the 2021 guidelines.[25] Thus, establishing that when the law is not adequate, governments can create parallel systems based on ethics and politics to achieve that which treaties can not.
Section 3: Case study, Lombok treasure return
In July 2023, the Netherlands formally returned 355 cultural objects, collectively known as the Lombok Treasure, to Indonesia.[26] These artifacts were looted in 1894 by the Dutch colonial army during the Lombok War from the palace of Cakranegara.[27] As the objects were taken more than a century before the Netherlands ratified the UNESCO 1970 Convention in 2009, they fell entirely outside the treaty’s reach.[28] Instead, restitution was pursued under the 2021 guidelines for colonial collections, a national policy framework that requires proof of ‘involuntary loss under colonial conditions,’ a standard that was met through detailed provenance research.[29] The return was unconditional and was coordinated through a Dutch advisory committee, operating outside of treaty-based diplomatic channels.
In the official restitution process, UNESCO 1970 was not invoked as a legal basis. The Dutch government pointed instead to the recommendations of its Advisory Committee on Colonial Collections and the national policy framework.[30] The justification centred explicitly on historical injustice, citing that the objects were ‘taken under duress,’ and framed the return as an act of ethical responsibility rather than compliance with international treaty obligations.[31] This approach reveals that UNESCO 1970 plays no substantive legal role in Dutch colonial restitution practice. The Lombok case clearly demonstrates the operational gap between international treaty law and national policy when addressing colonial-era takings. It highlights that the Netherlands has created a separate, ethics-driven pathway for restitution. One that functions where conventional heritage law remains silent. This real world example confirms that colonial returns are being handled as matters of historical justice and political dialogue, not as legal obligations under UNESCO 1970.
Section 4: Critical analysis
UNESCO 1970 offers no real legal path for returning colonial-era objects. The Lombok return shows the treaty’s limits. The treaty condemns theft in theory, but its time limits and legal definitions leave colonial injustices uncovered.[32] While the treaty provides no direct legal basis for colonial restitution, it does offer an indirect or normative influence. It shapes global discourse on heritage ethics and establishes standards that states may refer to when making moral arguments about restitution.[33] However, the Lombok case clearly illustrates that this normative role does not translate into future obligation.[34] The Dutch government did not treat UNESCO 1970 as the authoritative legal framework, rather, it acted under a separate, self-imposed ethical policy, which itself acknowledges the Convention’s shortcomings.
Relying on policy rather than law introduces three issues. First, volatility. Policies can shift with political changes, unlike binding treaty obligations. A change in government or public opinion could alter the criteria or willingness for restitution, leaving claims subject to fluctuating political will. Second, inconsistency. Without fixed legal rules, similar claims could be resolved in unequal ways, depending on who reviews them. One advisory committee might interpret ‘involuntary loss’ broadly, while another might apply it narrowly, leading to arbitrary outcomes that undermine the fairness and predictability of the process. Third, limited recourse. As policies are not legally binding, claimant states cannot take the matter to court if their request is denied. They are left without judicial enforcement methods, which places the power to decide almost entirely in the hands of the former colonial power. This reliance on policy, while enabling initial progress, creates a fragile and potentially unjust foundation for long-term cultural justice.
Broader implication
Does this mean international cultural heritage law needs reform to address colonial injustice?
The Dutch-Indonesian restitution experience suggests that current international heritage law is structurally inadequate for addressing colonial injustice. Its focus on post-ratification conduct and traditional definitions of illicit trade renders it blind to the systemic and historically sanctioned takings of the colonial period.[35] To close this gap, two critical reforms must happen. First, a protocol or interpretive guidelines to UNESCO 1970 extending it to pre-ratification takings obtained under coercive colonial conditions. Such an addition would formally recognise that a taking can be illicit in a moral and historical sense, even if it was legalised by colonial power structures at the time. Second, a new international agreement focused on colonial-era objects, one that supports ethical returns while setting clear rules for research and resolving disputes. A dedicated multilateral instrument would provide a stable, predictable, and just framework that transcends individual national policies.
Without this change, restitution will remain a topic of political choice rather than legal entitlement. The process will continue to depend on the voluntary goodwill of former colonial states, replicating a power imbalance that the very act of restitution seeks to redress. True justice in cultural heritage requires moving from recommended ethical gestures to universally recognised legal rights. The Lombok Treasure is a historic step, but it also underscores that the international legal framework must evolve to ensure such returns are not acts of grace, but acts of law.[36]
Conclusion
The analysis of UNESCO 1970, Dutch policy, and the Lombok Treasure return confirms that the Convention is structurally ill-equipped to mandate colonial restitution. Its prospective application, narrow definitions, and procedural conditions systematically exclude historical injustices, forcing states like the Netherlands to create parallel ethical frameworks. While these policy-based initiatives enable progress, they introduce significant risks of inconsistency, volatility, and a lack of enforceable rights for claimant nations.
The Lombok case is not an isolated example but a revealing precedent. It demonstrates that meaningful redress for colonial-era takings operates in a legal vacuum, dependent on political will rather than binding law. Consequently, achieving just restitution requires going beyond ad-hoc policy. The international community must pursue substantive legal reform, ideally through a dedicated multilateral instrument, to transform colonial restitution from an act of political grace into a matter of enforceable legal right. Only then can cultural heritage law fully address the legacy of colonialism.
Bibliography
UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property (1970) 823 UNTS 231
City of Rotterdam Returns Colonial-era Art to Indonesia’ (Colonial Collections Consortium, 25 November 2024) https://www.colonialcollections.nl/en/2024/11/ accessed 28 January 2026
‘Culture Conventions the Netherlands ratified’ (Netherlands and You, 2024) https://www.netherlandsandyou.nl/web/unesco-paris/about-us/netherlands-unesco/culture-conventions-the-netherlands-ratified accessed 28 January 2026
Felwine Sarr and Bénédicte Savoy, The Restitution of African Cultural Heritage: Toward a New Relational Ethics (November 2018) 9–12
Cultural Heritage Agency of the Netherlands, ‘Policy in the Netherlands’ https://english.cultureelerfgoed.nl/topics/c/cultural-goods-from-a-colonial-context/policy-in-the-netherlands accessed 28 January 2026
Cultural Heritage Preservation Act (Netherlands) (1984/2002/2009)
[1] UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property (1970) 823 UNTS 231.
[2] 1970 UNESCO Convention, art 3, 7b), 15.
[3] ‘City of Rotterdam Returns Colonial-era Art to Indonesia’ (Colonial Collections Consortium, 25 November 2024) https://www.colonialcollections.nl/en/2024/11/ accessed 28 January 2026.
[4] Cultural Heritage Preservation Act (Netherlands) (1984/2002/2009).
[5] 1970 UNESCO Convention, art 2.
[6] n2, art.3.
[7] n2, art.6.
[8] n2, art.7b).
[9] n2, art.15.
[10] ‘Culture Conventions the Netherlands ratified’ (Netherlands and You, 2024) https://www.netherlandsandyou.nl/web/unesco-paris/about-us/netherlands-unesco/culture-conventions-the-netherlands-ratified accessed 28 January 2026.
[11] 1970 UNESCO Convention, art 3.
[12] Felwine Sarr and Bénédicte Savoy, The Restitution of African Cultural Heritage: Toward a New Relational Ethics (November 2018) 9–12.
[13] 1970 UNESCO Convention, art 7 b) ii).
[14] n2, art 7 b) ii).
[15] ibid.
[16] Cultural Heritage Preservation Act (Netherlands) (1984/2002/2009).
[17] Cultural Heritage Preservation Act (Netherlands) (1984/2002/2009), art. 14b), 16.
[18] Cultural Heritage Agency of the Netherlands, ‘Policy in the Netherlands’ https://english.cultureelerfgoed.nl/topics/c/cultural-goods-from-a-colonial-context/policy-in-the-netherlands accessed 28 January 2026.
[19] n21.
[20] n21.
[21] n21.
[22] 1970 UNESCO Convention, art 15.
[23] Cultural Heritage Preservation Act (Netherlands) (1984/2002/2009), art. 14b), 16.
[24] Cultural Heritage Preservation Act (Netherlands) (1984/2002/2009), art. 14b), 16.
[25] Cultural Heritage Agency of the Netherlands, ‘Policy in the Netherlands’ https://english.cultureelerfgoed.nl/topics/c/cultural-goods-from-a-colonial-context/policy-in-the-netherlands accessed 28 January 2026.
[26] Colonial Collections Consortium, ‘The city of Rotterdam has become the first in the Netherlands to return art objects from the colonial era to Indonesia’ https://www.colonialcollections.nl/en/2024/11/ accessed 28 January 2026.
[27] Colonial Collections Consortium, ‘The city of Rotterdam has become the first in the Netherlands to return art objects from the colonial era to Indonesia’ https://www.colonialcollections.nl/en/2024/11/ accessed 28 January 2026.
[28] ‘Culture Conventions the Netherlands ratified’ (Netherlands and You, 2024) https://www.netherlandsandyou.nl/web/unesco-paris/about-us/netherlands-unesco/culture-conventions-the-netherlands-ratified accessed 28 January 2026.
[29] Cultural Heritage Agency of the Netherlands, ‘Policy in the Netherlands’ https://english.cultureelerfgoed.nl/topics/c/cultural-goods-from-a-colonial-context/policy-in-the-netherlands accessed 28 January 2026.
[30] Cultural Heritage Agency of the Netherlands, ‘Policy in the Netherlands’ https://english.cultureelerfgoed.nl/topics/c/cultural-goods-from-a-colonial-context/policy-in-the-netherlands accessed 28 January 2026.
[31] ibid.
[32] 1970 UNESCO Convention, art 3, 7b), 15.
[33] UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property (1970) 823 UNTS 231.
[34] Colonial Collections Consortium, ‘The city of Rotterdam has become the first in the Netherlands to return art objects from the colonial era to Indonesia’ https://www.colonialcollections.nl/en/2024/11/ accessed 28 January 2026.
[35] 1970 UNESCO Convention, art 3, 7b), 15.
[36] Colonial Collections Consortium, ‘The city of Rotterdam has become the first in the Netherlands to return art objects from the colonial era to Indonesia’ https://www.colonialcollections.nl/en/2024/11/ accessed 28 January 2026.
