UN Malaysian Mission photographed after reporting its findings in North Borneo to then-Secretary General U Thant (third from the right). Image Source: UN Photo

But just as important as these historical documents is the question of how much weight they carry in today’s world.

These questions are especially relevant when viewed through the lens of modern law and diplomatic practice. Recently, Paul Cohen, the lead lawyer representing the Sulu heirs, argued that the French court’s decision to void an earlier arbitration award from a Spanish court—seen as a major legal win for Malaysia—frees the Sulu heirs from arbitration proceedings altogether. He further claimed that this would allow them to lease the territory to another country at will.

With such far-reaching claims over Sabah and its population, it is worth considering how historical treaties hold up against contemporary legal and political realities.

But why do historical treaties matter?

In many cases, the international community continues to recognize agreements originating in colonial times. Inheriting the obligations of a predecessor state—even a colonial power—provides a stable and recognizable basis for legitimate possession of territory. It also aligns with the principle of uti possidetis juris, a rule of customary international law which holds that newly independent states should retain the boundaries they had as former colonies.

Malaysia, as the legal successor to British Malaysia, also inherited the legal standing of the British North Borneo Company in its possession of Sabah.

Therefore, Malaysia, as the legal successor to British Malaysia, also inherited the legal standing of the British North Borneo Company (BNBC) in its possession of Sabah. Malaysia also assumed the BNBC’s obligation to continue annual payments to the Sulu heirs for possession of Sabah—an act Malaysia performed until an armed invasion by militants claiming to represent the defunct Sulu Sultanate in 2013. This succession of legal and administrative inheritance provided one basis for Malaysian legitimacy in Sabah.

Legitimacy through Self-Determination

Of course, Colonial and imperial treaties are often viewed as remnants of inequality and foreign dominance. A discomforting truth is that none of the historical treaties dating to the 1800s or early 1900s now being invoked as the basis for claims over Sabah reflected the consent of the local population. Instead, they were the product of decisions made by colonial administrators and monarchs.

In 1962, the Cobbold Commission—established to assess public opinion—found that the majority in Sabah and Sarawak supported joining the proposed Federation of Malaysia.

So what do the people of Sabah actually want? The principle of self-determination has underwritten the legitimacy of most modern states. This was especially true of the many states emerging in the complex post-colonial environment.

In 1962, the Cobbold Commission was established to navigate this challenge in North Borneo and assess public opinion in the diverse ethnic and cultural region. It found that the majority in Sabah and Sarawak supported joining the proposed Federation of Malaysia. This finding was later corroborated by a United Nations mission in 1963, dispatched by then-Secretary-General U Thant, paving the way for the formal creation of Malaysia.

The Sabah claim remains largely dormant in Filipino public discourse.

And what of the people in the modern-day Sulu archipelago or the Philippines? If the Sulu Sultanate as a historical, albeit defunct, entity is to be considered in the context of post-colonial self-determination, one might examine this question. Yet there appears to be limited public interest with no plebiscite or large scale survey held on this issue. Filipino political candidates tend to gain more traction when they speak forcefully about sovereignty in the West Philippine Sea and other pressing domestic issues. By contrast, the Sabah claim remains largely dormant in Filipino public discourse.

Still, recent elections have resurfaced Sabah as a limited political talking point to mixed reception. As recently as 2022, the Philippine government has maintained that the Sulu heirs’ Sabah claim is a “private affair” of the Sulu heirs rather than a matter of state.

Sovereignty and Effective Administration

Malaysia’s continued administration of Sabah for more than half a century also strengthens its claim under the legal principle of prescription. This principle has two branches: acquisitive prescription, where sovereignty is gained through peaceful, continuous administration, and extinctive prescription, where a claimant may lose its rights by failing to actively assert them over time.

In this regard, Sabah’s economic trajectory as an active part of Malaysia stands in contrast to the Sulu archipelago, and to the inconsistently pressed claim of the Philippines.

Generations of Sabahans have been raised and built their lives within the existing political framework. Any hypothetical change in sovereignty would risk uncertainty and disruption to the everyday lives of Sabah’s people.

REFERENCES

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