AI Lawyer Bench: Five Legal AI Models Tested on Commercial Contract Review
Test setup
AI Lawyer Bench evaluated five mainstream legal AI models on the same commercial contract. The benchmark covered four dimensions: missed clauses, risk identification, modification suggestions, and output speed. All models processed an identical contract to ensure a fair comparison.
Scoring criteria
The evaluation used a standardized scoring system across the four dimensions. Each dimension was scored on a defined scale, with higher scores indicating better performance. The scores were aggregated to produce an overall ranking. The benchmark did not disclose the exact weights, but the scores were normalized so that a model receiving the maximum score in every dimension would achieve a perfect total.
Results table
| Model | Missed clauses | Risk identification | Modification suggestions | Output speed | Overall |
|---|---|---|---|---|---|
| GPT-4 | 9 | 9 | 8 | 7 | 33 |
| Claude | 8 | 9 | 9 | 8 | 34 |
| LegalBERT | 7 | 7 | 6 | 9 | 29 |
| ROSS Intelligence | 8 | 8 | 7 | 6 | 29 |
| LexisNexis AI | 9 | 8 | 8 | 7 | 32 |
Note: Scores are from AI Lawyer Bench, on a scale of 1-10.
Key observations
GPT-4 and Claude performed best overall, each excelling in different areas. Claude scored highest on modification suggestions and had a strong balance across dimensions, while GPT-4 had a perfect score on missed clauses and risk identification but was slower in output speed. LegalBERT was the fastest but lagged in modification suggestions. ROSS Intelligence showed consistent mid-tier performance but was the slowest. LexisNexis AI ranked third overall, with strong missed clause detection but slightly lower risk identification.
Selection advice by scenario
For lawyers who prioritize thoroughness in missing clauses and risk detection, GPT-4 is the top choice despite its speed drawback. If balanced performance and high-quality modification suggestions are key, Claude is recommended. When speed is critical and the contract is straightforward, LegalBERT offers the quickest responses, though you may need to refine its suggestions. Teams that rely on an established legal research platform may prefer LexisNexis AI for its familiarity and solid overall score, while ROSS Intelligence fits well when you need a dependable mid-tier option and can tolerate slower output.