Introduction

Gil Gap-soon did not live to hear a South Korean court rule, for the third time in just over four years, that Japan cannot hide behind sovereign immunity for what was done to her. It fell to her son to stand in a Cheongju courtroom this April and receive a judgment that came eighty years after Japan’s surrender. Four months earlier, in a different courtroom, the International Court of Justice had quietly paused its own reckoning with the same underlying question — whether a state’s immunity survives the gravest violations of international law — pending Italy’s assurance that its courts would fall back into line with the Court’s 2012 answer: yes, it does. Two court systems, one doctrinal question, two irreconcilable answers.

Two Courts, One Question

“Comfort women” is itself a translation of the Imperial Japanese military’s own euphemism, “ianfu” — literally “comfort woman” — for a system its own wartime correspondence justified as reducing rape and venereal disease among troops. The UN’s 1996 report on the issue chose a blunter label: military sexual slavery. Words, like doctrines, are rarely neutral. Neither, it turns out, is immunity. In 2012 the International Court of Justice held that Germany retained immunity from Italian courts even for Nazi-era atrocities, because immunity is procedural and jus cogens is substantive — the two, the Court reasoned, do not conflict. Italy’s Constitutional Court disagreed in October 2014, ruling that Italian courts could keep hearing such claims regardless, since no rule of international law could be allowed to close off constitutionally guaranteed access to justice. Seoul’s own courts split along a similar fault line, across two separate lawsuits: one panel’s 2021 judgment read jus cogens as simply overriding immunity; a different suit’s 2023 appellate ruling, reversing an initial dismissal, carved out a narrower exception instead — for torts committed against a forum state’s own nationals, on its own soil, outside armed conflict. The doctrinal comparison is not new, and neither, now, is a postcolonial reading of the Korean split. Less examined is why the very doctrine both borrow from — jus cogens — was never built with these plaintiffs in mind either.

What Sovereign Equality Hides

Jus cogens sits somewhere in the reasoning of nearly every ruling in this story — explicitly in Korea’s first judgment, implicitly wherever a court had to decide these acts were grave enough that immunity might not survive them. That threshold is not neutral either. Jus cogens crystallised around harms states inflict on one another — aggression, genocide as state policy — while systematic sexual violence entered that catalogue only after decades of feminist argument, as Charlesworth and Chinkin showed in their landmark critique of the doctrine’s gendered architecture, itself a sequel to the essay that helped found the field. Even today, the International Law Commission’s own catalogue of peremptory norms omits gender-based discrimination as such. Courts reaching for jus cogens to rescue these plaintiffs are, in other words, reaching for a category their claims had to fight their way into.

“Sovereign equality” performs a parallel concealment. Treating Japan and Korea as two equally sovereign states before the law of immunity brackets out that Korea was Japan’s colony from 1910 to 1945, and that the 1965 and 2015 settlements were negotiated in the long shadow of that asymmetry — precisely the move Third World Approaches to International Law scholarship identifies at the foundation of the sovereignty concept itself, born of a “civilising mission” that classed non-European peoples as subjects to be governed rather than equals to be bargained with. Read together — as Kimberlé Crenshaw‘s intersectional framework insists they must be — these are not two critiques but one: a doctrine built to settle disputes between formally equal, gender-blind, colonially-blind states was never going to fit a claim that is about gender and empire at once.

None of this should flatten the women themselves into passive objects of law. It was Kim Hak-sun’s own decision, on 14 August 1991, to name herself publicly that broke five decades of silence and set every subsequent case in motion — a fact postcolonial feminists insist on, since even the most sympathetic human-rights narrative can quietly resurrect the “native” victim it means to rescue.

Conclusion

None of this answers what “sovereign equality” should mean between a former empire and the colony it once ruled — it only exposes that immunity’s claim to answer that question through formal symmetry is itself part of the problem. Germany’s second case against Italy remains suspended at the ICJ; the narrower exception Seoul’s appellate court carved out already has company, having drawn on a similar 2021 ruling from Brazil’s Supreme Court in the unrelated Changri-lá case — proof the doctrinal tool travels beyond colonial disputes, even where the deeper injustice traced here does not. Whether courts confronting claims rooted specifically in colonial rule — and there is no shortage of unresolved ones across the former colonial world — take up Seoul’s model will turn less on doctrine than on whether judges elsewhere ask Seoul’s question instead of The Hague’s: not whether immunity is theoretically reconcilable with jus cogens, but who it has always, in practice, protected. Gil Gap-soon never got to put that question to a court herself. Her case did.