Introduction

Over time, the relationship between municipal law and international law has been a topic of debate, with each being considered superior to the other at different points. Various theories have emerged to explore this relationship, with jurists offering perspectives that either emphasize the dominance of one over the other or highlight their independence. The key debate centers on whether international law and municipal law should be seen as a single, unified legal system or as distinct, separate entities. This debate has given rise to two main theories: monism and dualism.

Monists view international law and municipal law as part of a single, cohesive legal framework. In contrast, dualists argue that international law only becomes part of municipal law when it is explicitly incorporated into national legislation. The following theories further explore the dualistic perspective on the application of international law within the context of municipal law.

Theory of Specific Adoption or Transformation

According to the theory of dualism, a relationship between international law and municipal law is established when international law is not automatically applicable within a state’s legal system. Instead, it must be transformed or specifically adopted into the municipal law of the state. This theory emphasizes that international law should not merely be incorporated but must be actively transformed or adopted into the municipal legal framework.

The key difference here lies in the process: while incorporation means that international law becomes part of municipal law simply because it is necessary, transformation requires a deliberate act by the state to adopt it into its national legal system. Under incorporation, international law automatically becomes the law of the land, whereas in transformation theory, international law only becomes national law when it is consciously included in the legislature. This is especially relevant for treaties, which, according to transformation theory, must be converted into statutes to be binding under municipal law.

The core idea is that for international law to be recognized as national law by courts, the legislature must transform it into a rule of the state. This process is essential for international law to have legal standing within the country. The theory argues that without this transformation, international law cannot be treated as law within the municipal legal system.

However, this theory has faced criticism, particularly from monists, who argue that the difference between treaties and statutes is procedural rather than substantive. They contend that it is incorrect to say that treaties require transformation to be binding under municipal law. Moreover, the notion that international law binds states while municipal law binds individuals is also challenged as a flawed distinction.

In summary, the theory of specific adoption or transformation suggests that international law only becomes applicable within a sovereign state when the state explicitly adopts it through legislative action. This theory underscores the idea that for international law to have an impact at the national level, it must be intentionally enacted as part of the state's legal framework.

Delegation Theory

This theory emerged as a response to criticisms of the transformation theory. Monists developed the delegation theory, arguing that each state or sovereign has the inherent right, established by international law, to determine the extent to which international law is applied within its jurisdiction. This concept is referred to as the "constitutional rules of international law" or treaties, which allow states to decide when and to what extent international laws should be implemented in their territory, depending on their incorporation into municipal law.

Unlike the transformation theory, delegation theory suggests that there is no need for the specific adoption or transformation of international law into national law. Instead, states accept a single act that brings international rules into effect as needed, without incorporating new rules directly into state law. The responsibility for enacting laws that benefit the state lies with the legislature, and under this theory, the state can implement international law according to its specific needs and requirements.

Critics of this theory argue that it is a reaction against dualism, but it also has its own issues. One major criticism is the ambiguity surrounding the term "constitutional rules of international law," which creates confusion in defining the theory. Additionally, while the theory emphasizes the supremacy of international law, it often fails to clarify the relationship between international and municipal laws. Critics also point out that the theory's suggestion that national laws would not yield to international rules seems unrealistic and unjust. Furthermore, the theory does not fully recognize the sovereignty of each state, which is a significant point of contention.