Facts of the Case
Two neighbouring states, X and Y, signed a bilateral treaty many years ago. This treaty clearly defined the demarcation of boundary between them. Despite this, for several years, State Y maintained a physical boundary line that differed from the one in the treaty. Interestingly, State X allowed this to continue without objection or protest.
This tolerance from X spanned decades, during which Y developed infrastructure, governance, and population settlements in the contested zone. The area appeared to have become de facto territory of Y. But after many years, X suddenly raised an objection and claimed that Y violated the original treaty terms.
Now, the question arises: Can Y defend its actions, even when the written treaty contradicts its claims?
Issues in the Case
- Did ‘X’ legally forfeit its treaty rights by not objecting for many years?
- Can ‘Y’ claim sovereignty over the disputed territory based on prolonged control and acquiescence?
- Does international law support a defence of acquiescence against a formal treaty?
- Is the demarcation of boundary open to re-interpretation through conduct and silence?
Legal Principles and Precedents
1. Principle of Acquiescence
In international law, acquiescence refers to the passive acceptance or tolerance of a situation by a state. When a state observes another state’s conduct and remains silent for a long time, it may lose its right to object later.
In the Island of Palmas Case (1928), the tribunal held that continuous and peaceful display of authority by one state, unchallenged by another, could lead to recognition of sovereignty. Similarly, in the Eastern Greenland Case (1933), the court recognised Denmark’s claim based on Norway’s earlier silence.
2. Estoppel in International Law
Estoppel prevents a state from contradicting its earlier position if another party has relied upon that conduct to its detriment. If Y made investments and developed the area based on X’s inaction, X may be estopped from enforcing the original boundary.
3. Effectivity Principle
Effectivity is the actual exercise of state authority over a territory. If Y administered the region and exercised control without opposition from X, that could support Y‘s claim.
Judgment and Possible Outcome
A tribunal or international court examining this case would consider several factors. While treaties are binding, the court would also assess the long-standing practice and conduct of both states.
Given that:
- X knowingly tolerated Y’s different demarcation of boundary,
- Y established clear and peaceful authority over the territory,
- X made no timely objection,
- And Y acted in reliance on X‘s silence,
The court may likely rule in favour of Y. It would conclude that X, through years of acquiescence, waived its right to enforce the original treaty terms.
Thus, the demarcation of boundary that reflects ground realities and administrative control may be upheld over a historic treaty map, especially if that map was effectively abandoned in practice.
