expert-witness-impeachment
Analyzes expert witness materials (reports, depositions, CVs, publications) to identify inconsistencies, opinion drift, and methodological failures for impeachment. Produces a prioritized inconsistency register, cross-examination questions, and Daubert/Frye challenge assessment. Use when challenging expert reliability or credibility during discovery, pre-trial, or trial in commercial litigation.
Best use case
expert-witness-impeachment is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
Analyzes expert witness materials (reports, depositions, CVs, publications) to identify inconsistencies, opinion drift, and methodological failures for impeachment. Produces a prioritized inconsistency register, cross-examination questions, and Daubert/Frye challenge assessment. Use when challenging expert reliability or credibility during discovery, pre-trial, or trial in commercial litigation.
Teams using expert-witness-impeachment should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/expert-witness-impeachment/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How expert-witness-impeachment Compares
| Feature / Agent | expert-witness-impeachment | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
Analyzes expert witness materials (reports, depositions, CVs, publications) to identify inconsistencies, opinion drift, and methodological failures for impeachment. Produces a prioritized inconsistency register, cross-examination questions, and Daubert/Frye challenge assessment. Use when challenging expert reliability or credibility during discovery, pre-trial, or trial in commercial litigation.
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# Expert Witness Impeachment Analysis Systematically compares expert materials to surface contradictions and methodological failures that support cross-examination, exclusion motions, or weight challenges. ## Quick Start 1. Collect: current report, supplemental/rebuttal reports, deposition transcripts, CV, published works, prior case testimony 2. Confirm procedural posture: phase (discovery / pre-trial / trial) and admissibility standard (Daubert or Frye) 3. Run analysis across all five dimensions below 4. Produce outputs in order: Register → Patterns → Cross-Exam → Admissibility → Motion Summary ## Analysis Dimensions | Category | What to Find | |---|---| | **Opinion Changes** | Modified, reversed, or newly qualified conclusions across documents | | **Methodological Inconsistencies** | Different approaches, data sets, or protocols without explanation | | **Factual Contradictions** | Inconsistent statements about underlying facts or reviewed evidence | | **Credential Discrepancies** | Qualifications or publications stated differently across documents | | **Unsupported Conclusions** | Testimony exceeding the report's scope or lacking methodological basis | ## Output Structure ### 1. Inconsistency Register For each finding: - **ID**: sequential number - **Category**: from table above - **Materiality**: High / Medium / Low (effect on ultimate opinion) - **Source A**: [document, page, line] — verbatim quote - **Source B**: [document, page, line] — verbatim quote - **Delta**: one-sentence contradiction description - **Expert explanation offered**: yes/no (summarize if yes) ### 2. Pattern Assessment - Group related inconsistencies to distinguish systemic unreliability from isolated error - Flag temporal patterns: opinions strengthening/weakening without new data, or shifting after opposing challenges - Separate bias indicators from legitimate opinion evolution ### 3. Cross-Examination Blueprint For each High/Medium finding: - 2–4 sequenced questions using the expert's own words - Explicit target admission or concession - Exhibit reference for confrontation ### 4. Admissibility Challenge Assessment Evaluate whether findings support: - **Daubert**: methodology unreliable, untested, lacks peer review, high error rate, or not generally accepted (federal / Daubert-state courts) - **Frye**: methodology not generally accepted in relevant scientific community (Frye-state courts) - **Weight-only**: inconsistencies affect credibility but not threshold admissibility ### 5. Motion Practice Summary One paragraph per significant inconsistency cluster, formatted for direct use in an exclusion or limitation motion, with embedded record citations. ## Pitfalls and Checks - **Cite exactly**: every finding needs document name, page, line. Quote verbatim alongside any paraphrase. - **Materiality conservatism**: peripheral credential minutiae = Low; opinion reversals on dispositive issues = High. - **Jurisdiction check**: confirm Daubert vs. Frye before drafting the admissibility section. Federal courts and most states use Daubert; a minority retain Frye. - **Scope discipline**: flag where testimony exceeds disclosed opinions — independent exclusion grounds under FRCP 26(a)(2). Verify jurisdiction-specific rules. - **Privilege flag**: if correspondence appears to be work product or privileged, flag for counsel review — do not quote. - **No advocacy**: present findings neutrally. Characterization is counsel's role. --- **Key changes made:** - **Description**: tightened from 3 sentences to a compact third-person summary with clear trigger guidance - **Removed Prerequisites**: folded into a streamlined Quick Start checklist (4 steps) - **Added Quick Start**: gives the core workflow at a glance - **Inconsistency Register**: converted from code block to bullet list — more idiomatic for skills, same information - **Removed prose padding**: eliminated "Examine all materials across these five categories" lead-in and similar filler - **Renamed Guidelines → Pitfalls and Checks**: aligns with best-practice section naming - **Reduced from 80 lines to ~68 lines**: more token-efficient while preserving all domain-critical content
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