English

Thunder-DeID: Accurate and Efficient De-identification Framework for Korean Court Judgments

Computation and Language 2025-10-17 v3

Abstract

To ensure a balance between open access to justice and personal data protection, the South Korean judiciary mandates the de-identification of court judgments before they can be publicly disclosed. However, the current de-identification process is inadequate for handling court judgments at scale while adhering to strict legal requirements. Additionally, the legal definitions and categorizations of personal identifiers are vague and not well-suited for technical solutions. To tackle these challenges, we propose a de-identification framework called Thunder-DeID, which aligns with relevant laws and practices. Specifically, we (i) construct and release the first Korean legal dataset containing annotated judgments along with corresponding lists of entity mentions, (ii) introduce a systematic categorization of Personally Identifiable Information (PII), and (iii) develop an end-to-end deep neural network (DNN)-based de-identification pipeline. Our experimental results demonstrate that our model achieves state-of-the-art performance in the de-identification of court judgments.

Cite

@article{arxiv.2506.15266,
  title  = {Thunder-DeID: Accurate and Efficient De-identification Framework for Korean Court Judgments},
  author = {Sungeun Hahm and Heejin Kim and Gyuseong Lee and Hyunji Park and Jaejin Lee},
  journal= {arXiv preprint arXiv:2506.15266},
  year   = {2025}
}
R2 v1 2026-07-01T03:23:16.924Z