Multi-Legal-Bench: Evaluating LLMs on Legal Reasoning Across Jurisdictions, Languages, and Legal Traditions
- URL: http://arxiv.org/abs/2605.29738v1
- Date: Thu, 28 May 2026 10:31:37 GMT
- Title: Multi-Legal-Bench: Evaluating LLMs on Legal Reasoning Across Jurisdictions, Languages, and Legal Traditions
- Abstract summary: Multi-Legal-Bench is the first cross-jurisdictional legal benchmark that evaluates identical tasks across six countries.<n> benchmark defines five tasks court-type classification, judgment form classification, case-outcome prediction, legal norm extraction, and cause category prediction.<n>We evaluate 7 frontier LLMs under zero-shot and 3-shot prompting via AWS Bedrock, with 4 additional small/medium models (3-12B) for scaling analysis.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Legal NLP benchmarks overwhelmingly evaluate a single language or aggregate tasks that differ fundamentally across jurisdictions, making cross-lingual comparison impossible. We introduce Multi-Legal-Bench, the first cross-jurisdictional legal benchmark that evaluates identical tasks across six countries (Ukraine, France, Netherlands, Poland, Czech Republic, Lithuania), four language families, and 134 million court decisions. The benchmark defines five tasks court-type classification, judgment form classification, case-outcome prediction, legal norm extraction, and cause category prediction mapped to structured metadata from national court registries, forming a deliberately sparse 5x6 task-jurisdiction matrix (20 of 30 cells filled). We evaluate 7 frontier LLMs under zero-shot and 3-shot prompting via AWS Bedrock, with 4 additional small/medium models (3-12B) for scaling analysis. Our results reveal that: (1) task-dependent few-shot effects discovered in Ukrainian replicate across all jurisdictions; (2) no single model dominates any language rankings shift with both task and jurisdiction; (3) cross-lingual few-shot transfer does not follow language proximity: UA->FR (Romance, -2.1 pp) transfers better than UA->PL (Slavic, -13.7 pp), with label-set alignment predicting transfer quality better than language family; and (4) tokenizer fertility, despite a 2.3x spread, does not significantly predict cross-lingual accuracy (r=-0.27, p=0.14), suggesting that model architecture and pretraining data dominate tokenizer efficiency. We release all data, prompts, and model predictions.
Related papers
- Inference-Time Steering for Cross-Lingual Factual Consistency in LLMs [51.56484100374058]
Large Language Models (LLMs) demonstrate remarkable multilingual fluency, but their internal knowledge representations remain disproportionately biased toward high-resource languages.<n>We investigate whether these biases can be mitigated at inference time, forcing an English-prompted model to answer as if it were queried in target languages.<n>Experiments on Gemma 3 12B Instruct reveal persona prompting to be the strongest overall intervention, balancing efficacy, safety, and out-of-domain generalization.
arXiv Detail & Related papers (2026-07-21T16:15:05Z) - UA-Legal-Bench: A Benchmark for Evaluating Large Language Models on Ukrainian Legal Reasoning [0.0]
We introduce UA-Legal-Bench, a five-task benchmark for evaluating large language models on Ukrainian legal reasoning.<n>We evaluate 11 LLMs from five families under zero-shot and 3-shot prompting via AWS Bedrock with 158K API calls.<n>Our results reveal sharply task-dependent few-shot effects: few-shot prompting improves judgment form classification by up to +38.6 pp but has mixed effects on outcome prediction.
arXiv Detail & Related papers (2026-05-27T23:12:20Z) - Tokenizer Fertility and Zero-Shot Performance of Foundation Models on Ukrainian Legal Text: A Comparative Study [0.0]
Tokenizer fertility varies 1.6x across foundation models on Ukrainian legal text.<n>Qwen 3 models consume 60% more tokens than Llama-family models on identical input.<n>Few-shot degrades performance by up to 26 percentage points.
arXiv Detail & Related papers (2026-05-14T14:35:05Z) - LegalBench-BR: A Benchmark for Evaluating Large Language Models on Brazilian Legal Decision Classification [0.0]
We introduce LegalBench-BR, the first public benchmark for evaluating language models on Brazilian legal text classification.<n>The dataset comprises 3,105 appellate proceedings from the Santa Catarina State Court (TJSC)<n>On a class-balanced test set, BERTimbau-LoRA achieves 87.6% accuracy and 0.87 macro-F1 (+22pp over Claude 3.5 Haiku, +28pp over GPT-4o mini)
arXiv Detail & Related papers (2026-04-20T22:00:02Z) - Swiss-Bench SBP-002: A Frontier Model Comparison on Swiss Legal and Regulatory Tasks [0.0]
No existing benchmark evaluates frontier model performance on applied Swiss regulatory tasks.<n>I introduce Swiss-Bench SBP, a trilingual benchmark of 395 expert-crafted items spanning three Swiss regulatory domains.<n>I evaluate ten frontier models from March 2026 using a structured three-dimension scoring framework.
arXiv Detail & Related papers (2026-03-24T18:41:07Z) - Evaluating Modern Large Language Models on Low-Resource and Morphologically Rich Languages:A Cross-Lingual Benchmark Across Cantonese, Japanese, and Turkish [12.286855282078305]
GPT-4o, GPT-4, Claude3.5Sonnet, LLaMA3.1, MistralLarge2, LLaMA-2Chat13B, and Mistral7BInstruct are evaluated.<n>Our benchmark spans four diverse tasks: open-domain question answering, document summarization, English-to-X translation, and culturally grounded dialogue.
arXiv Detail & Related papers (2025-11-05T22:09:53Z) - A Multi-Language Object-Oriented Programming Benchmark for Large Language Models [61.267115598083315]
A survey of 35 existing benchmarks uncovers three major imbalances.<n>85.7% focus on a single programming language.<n>94.3% target only function-level or statement-level tasks.<n>Over 80% include fewer than ten test cases on average.
arXiv Detail & Related papers (2025-09-30T11:30:08Z) - Breaking Language Barriers in Multilingual Mathematical Reasoning: Insights and Observations [59.056367787688146]
This paper pioneers exploring and training powerful Multilingual Math Reasoning (xMR) LLMs.
We construct the first multilingual math reasoning instruction dataset, MGSM8KInstruct, encompassing ten distinct languages.
By utilizing translation, we construct the first multilingual math reasoning instruction dataset, MGSM8KInstruct, encompassing ten distinct languages.
arXiv Detail & Related papers (2023-10-31T08:09:20Z) - OneAligner: Zero-shot Cross-lingual Transfer with One Rich-Resource
Language Pair for Low-Resource Sentence Retrieval [91.76575626229824]
We present OneAligner, an alignment model specially designed for sentence retrieval tasks.
When trained with all language pairs of a large-scale parallel multilingual corpus (OPUS-100), this model achieves the state-of-the-art result.
We conclude through empirical results and analyses that the performance of the sentence alignment task depends mostly on the monolingual and parallel data size.
arXiv Detail & Related papers (2022-05-17T19:52:42Z) - A Survey on Legal Judgment Prediction: Datasets, Metrics, Models and
Challenges [73.34944216896837]
Legal judgment prediction (LJP) applies Natural Language Processing (NLP) techniques to predict judgment results based on fact descriptions automatically.
We analyze 31 LJP datasets in 6 languages, present their construction process and define a classification method of LJP.
We show the state-of-art results for 8 representative datasets from different court cases and discuss the open challenges.
arXiv Detail & Related papers (2022-04-11T04:06:28Z) - Few-shot Learning with Multilingual Language Models [66.49496434282564]
We train multilingual autoregressive language models on a balanced corpus covering a diverse set of languages.
Our largest model sets new state of the art in few-shot learning in more than 20 representative languages.
We present a detailed analysis of where the model succeeds and fails, showing in particular that it enables cross-lingual in-context learning.
arXiv Detail & Related papers (2021-12-20T16:52:35Z) - AmericasNLI: Evaluating Zero-shot Natural Language Understanding of
Pretrained Multilingual Models in Truly Low-resource Languages [75.08199398141744]
We present AmericasNLI, an extension of XNLI (Conneau et al.), to 10 indigenous languages of the Americas.
We conduct experiments with XLM-R, testing multiple zero-shot and translation-based approaches.
We find that XLM-R's zero-shot performance is poor for all 10 languages, with an average performance of 38.62%.
arXiv Detail & Related papers (2021-04-18T05:32:28Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.