A Comparative Study of Summarization Algorithms Applied to Legal Case Judgments

  • Paheli BhattacharyaEmail author
  • Kaustubh Hiware
  • Subham Rajgaria
  • Nilay Pochhi
  • Kripabandhu Ghosh
  • Saptarshi Ghosh
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11437)


Summarization of legal case judgments is an important problem because the huge length and complexity of such documents make them difficult to read as a whole. Many summarization algorithms have been proposed till date, both for general text documents and a few specifically targeted to summarizing legal documents of various countries. However, to our knowledge, there has not been any systematic comparison of the performances of different algorithms in summarizing legal case documents. In this paper, we perform the first such systematic comparison of summarization algorithms applied to legal judgments. We experiment on a large set of Indian Supreme Court judgments, and a large variety of summarization algorithms including both unsupervised and supervised ones. We assess how well domain-independent summarization approaches perform on legal case judgments, and how approaches specifically designed for legal case documents of other countries (e.g., Canada, Australia) generalize to Indian Supreme Court documents. Apart from quantitatively evaluating summaries by comparing with gold standard summaries, we also give important qualitative insights on the performance of different algorithms from the perspective of a law expert.


Summarization Legal case judgment Supervised Unsupervised 



We sincerely acknowledge Prof. Uday Shankar and Uma Jandhyala from Rajiv Gandhi School of Intellectual Property Law, Indian Institute of Technology Kharagpur, India for their valuable feedback.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Paheli Bhattacharya
    • 1
    Email author
  • Kaustubh Hiware
    • 1
  • Subham Rajgaria
    • 1
  • Nilay Pochhi
    • 1
  • Kripabandhu Ghosh
    • 2
  • Saptarshi Ghosh
    • 1
  1. 1.Indian Institute of Technology KharagpurKharagpurIndia
  2. 2.Indian Institute of Technology KanpurKanpurIndia

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