The notion of denial of justice is at the heart of the theory of international liability of sovereign states. For centuries, sovereigns have endeavored to guarantee that their nationals established in foreign land receive a minimum degree of protection. And few acts are more offensive to sovereignty than a refusal to render justice, which “[i]n earlier times” was a “just cause of war.”
Beyond this seemingly straightforward principle hides a doctrine of elusive character. Some have attempted, in vain, to codify the main features of a denial of justice. But the “notion of denial of justice . . . seems to defy any definition.” This notion instead benefits from a judgment of “what is fair and equitable” in the circumstances of individual cases and cannot be defined “in the abstract.”
The notion of denial of justice is thus particularly prone to a casuistic analysis under customary international law. Defined as the general and consistent practice of States that they follow from a sense of legal obligation, customary international law covers State practice that is “extensive and virtually uniform.” It includes “diplomatic acts and instructions” as well as “statements of policy,” is “inherently flexible,” and “evolv[es]” over time.