Complexity and Entropy in Legal Language
Open accessAbstract
We study the language of legal codes from different countries and legal traditions, using concepts from physics, algorithmic complexity theory and information theory. We show that vocabulary entropy, which measures the diversity of the author’s choice of words, in combination with the compression factor, which is derived from a lossless compression algorithm and measures the redundancy present in a text, is well suited for separating different writing styles in different languages, in particular also legal language. We show that different types of (legal) text, e.g. acts, regulations or literature, are located in distinct regions of the complexity-entropy plane, spanned by the information and complexity measure. This two-dimensional approach already gives new insights into the drafting style and structure of statutory texts and complements other methods.
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Legal language is notoriously complex.
“Legal language is notoriously complex [3–5]”
From GPT-4 passes the bar exam (2024) · cites this paper as [3]
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Cited by
Sorted by citations
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- Authors
- Friedrich, R.
- Affiliations
- ETH Zurich (CH)
- Corresponding author
- Friedrich, Roland
- Venue
- Frontiers in Physics
- Publisher
- Frontiers Media SA
- Published
- 2021-06-04
- Volume
- 9
- ISSN
- 2296-424X (ISSN-L)
- OpenAlex
- W3168273140
- Cited by
- 19
- References
- 39
- Citations by year
- 2026: 4 · 2025: 4 · 2024: 6 · 2023: 3 · 2022: 1 · 2021: 1
- FWCI
- 0.97
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- Frontiers in Physics (publishedVersion, cc-by)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Repository for Publications and Research Data (ETH Zurich) (submittedVersion, cc-by)
- ETH Zürich Research Collection (cc-by)
- Funders
- Harvard University
- Eidgenössische Technische Hochschule Zürich
- Max-Planck-Institut für Physik Komplexer Systeme
- Topics
- Physical Sciences › Computer Science › Artificial Intelligence › Authorship Attribution and Profiling
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Fractal and DNA sequence analysis
- Social Sciences › Law › Legal Language and Interpretation
- Keywords
- legal language, legal codes, algorithmic complexity, lossless compression, statutory text, legal tradition, information theory
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