Antidote.

Legal reasoning

LegalBench

162 legal reasoning tasks spanning issue-spotting, rule recall, application, conclusion, interpretation, and rhetorical understanding.

As of 13 August 2026. Conditional pack. Guha et al. 2023. Per-task licenses are not inherited from the repository. A single LegalBench macro score is refused.

LegalBench is 162 tasks from 36 sources spanning issue-spotting, rule recall, application, conclusion, interpretation, and rhetorical understanding. Category scores stay separate because they are different skills. Interpretation includes CUAD-style clause classification, which is easier than span extraction.

Rule-application is graded twice: correctness and analysis. A right outcome without the inference is a different product failure than a wrong outcome. Slice tables with n of 12 to 29 are maps of where models diverge, not population estimates. GPT-4, GPT-3.5, and Claude-1 here are 2023 retrievals, not a 2026 frontier ladder.

Scale
162 tasks from 36 sources, including CUAD-derived clause classification
Provenance
Guha et al. 2023, Stanford LegalBench site, arXiv 2308.11462. Task licenses are not inherited from the repository.
Contamination
High. Public since 2023. Per-task licenses are composite and must be approved before a run.
Cannot establish
Legal correctness in a client matter, Harvey product performance, or a vendor moat. A single LegalBench macro score is refused.

Metrics, kept separate

  • Balanced accuracy by reasoning category
  • Rule-application correctness
  • Rule-application analysis
  • Task-specific official metrics

Paper table · Guha et al., 2023 · not an Antidote run · not a product score

LegalBench commercial models by reasoning category

Guha et al., 2023, Table 2. Balanced accuracy within each reasoning category. GPT-4, GPT-3.5 (text-davinci-003), and Claude-1, retrieved May to August 2023. Not a single LegalBench winner score.

Reasoning categoryGPT-4GPT-3.5Claude-1
Issue-spotting82.9%60.9%58.1%
Rule recall59.2%46.3%57.7%
Rule conclusion89.9%78%79.5%
Interpretation75.2%72.6%67.4%
Rhetorical79.4%66.7%68.9%

Paper table · Guha et al., 2023 · not an Antidote run · not a product score

LegalBench rule-application correctness and analysis

Guha et al., 2023, Table 3. Correctness and analysis are graded separately. A correct outcome without analysis is a different failure than an incorrect outcome.

SystemCorrectnessAnalysis
GPT-482.2%79.7%
Claude-161.4%59%
GPT-3.558.5%44.2%

Paper table · Guha et al., 2023 · not an Antidote run · not a product score

Hearsay slices, GPT-3.5 vs GPT-4

Guha et al., 2023, Table 6. Slice n is 12 to 29. These percentages show where the models diverge, not a population estimate.

SlicenGPT-3.5GPT-4
Non-assertive conduct19100%100%
In-court statement1457%93%
Standard hearsay2997%97%
Non-verbal hearsay1233%75%
Not for truth2025%45%

What the figures bound

GPT-4 is 82.9% on issue-spotting and 59.2% on rule recall. Rule conclusion is 89.9%; interpretation 75.2%; rhetorical understanding 79.4%. GPT-3.5 and Claude-1 are close to each other on several categories and far from GPT-4 on issue-spotting. Rule-application correctness is 82.2% for GPT-4 and 58.5% for GPT-3.5; analysis is 79.7% and 44.2%.

Hearsay slices show the same refusal to average: GPT-4 lifts non-verbal hearsay from 33% to 75% and in-court statements from 57% to 93%, while both models remain weak when the statement is not offered for its truth (25% vs 45%). These are 2023 model diagnostics. They do not score Harvey, and they do not decide legal correctness in a client matter.

What this page does not conclude

  • Legal correctness on a client matter
  • Harvey or any legal-product performance
  • A 2026 frontier ranking
  • A LegalBench macro winner

Cited as calibration on these memos — not a score of those products.