Of course. An expert witness report is a critical document in the litigation process. A thorough review is essential to ensure it is robust, credible, and effective.

Here is a comprehensive guide to reviewing an expert witness report, broken down into key areas of focus. This guide is useful whether you are the retaining attorney assessing your own expert's work, the opposing counsel looking for weaknesses, or an expert conducting a self-review.

The Ultimate Expert Witness Report Review Checklist

A high-quality report should be clear, concise, logically sound, and legally compliant. Use this checklist to methodically evaluate any report.

1. Foundation & Admissibility (The "Daubert/Frye" Check)

This is the most critical section. A report that doesn't meet these standards can be excluded entirely.

• Qualifications: Does the report clearly establish the expert's qualifications to opine on the specific topics?


• Is the CV attached and up-to-date?


• Do the qualifications directly relate to the issues in the case?


• Is there any "stretching" of expertise into unrelated areas?


• Reliability of Methodology: Is the expert's methodology scientifically valid and reliably applied?


• Is the methodology clearly explained and not just stated?


• Is it a methodology accepted within the relevant professional community?


• Has the methodology been tested and peer-reviewed?


• What is the known or potential error rate?


• Are the data and materials relied upon appropriate and sufficient for the conclusions drawn?


• Fit: Do the opinions directly address the facts of the case and the relevant legal questions?


• Are the conclusions relevant to the claims or defenses?


• Is there a direct connection between the analysis and the ultimate opinions?

2. Structural & Formal Requirements

The report must comply with procedural rules (e.g., Federal Rule of Civil Procedure 26(a)(2)(B)).

• Complete Signature & Date: Is the report signed and dated by the expert?


• Statement of Compensation: Does it include a statement of what the expert is being paid for the study and testimony? (This is a mandatory FRCP 26 requirement).


• List of Materials Reviewed: Is there a complete list of all data, documents, and other information the expert considered?


• Is the list specific? (e.g., "Deposition of Jane Doe, dated January 15, 2024," not just "various discovery documents").


• Are all key documents cited in the analysis included in this list?


• List of Prior Testimony: (FRCP 26 requirement) Has the expert provided a list of other cases in the past four years where they testified as an expert?

3. Clarity, Logic, & Substance

This is the heart of the report—is it persuasive and well-reasoned?

• Executive Summary/Conclusion Section: Can a layperson (judge or juror) understand the bottom-line opinions just by reading the first page or two?


• Factual Foundation: Are the facts and assumptions upon which the opinions are based clearly stated?


• Are the assumptions reasonable and supported by evidence?


• If facts are in dispute, does the expert acknowledge alternative scenarios?


• Transparent Analysis: Is the "path" from data to conclusion easy to follow?


• Are calculations shown?


• Are methodologies described step-by-step?


• Is the language clear and free of unnecessary jargon? When jargon is necessary, is it defined?


• Logical Flow: Do the conclusions flow logically and inevitably from the analysis?


• Are there logical leaps or unsupported inferences?


• Are all opinions supported by the analysis within the report itself?


• Addressing Counterarguments: Does the report anticipate and address likely alternative explanations or criticisms from the opposing side? A strong report often inoculates itself against attack.


• Neutral & Objective Tone: Does the expert maintain an objective, impartial tone, or does the language sound like advocacy? The most credible experts are educators, not partisans.

4. Critical Review for the Retaining Attorney

When reviewing your own expert's draft report, ask these additional questions:

• Strategic Alignment: Does the report perfectly support your theory of the case?


• Strengths & Weaknesses: What are the report's greatest strengths? What are its most vulnerable points? How can you shore them up?


• Deposition & Cross-Examination Prep: What questions will the opposing counsel ask about this report? Is the expert prepared to defend every sentence?


• Visual Aids: Does the analysis lend itself to clear, understandable charts, graphs, or animations for trial?

5. Critical Review for the Opposing Counsel

When reviewing the opposing expert's report, your goal is to find vulnerabilities for a Daubert challenge or for effective cross-examination.

• Scrutinize the Materials Reviewed: Are there glaring omissions? Did they fail to review key documents that would undermine their opinion?


• Attack Assumptions: Are their core assumptions contradicted by the evidence?


• Check for Internal Inconsistencies: Does the expert contradict themselves within the report?


• Investigate the Expert: Does their published work, prior testimony, or academic writing contradict the opinions in this report?


• Overstated Conclusions: Do the conclusions overreach what the analysis can support? Look for phrases like "proves," "establishes," or "confirms" when the data only supports "suggests" or "is consistent with."


• Bias/Compensation: Is the fee structure unusually high, suggesting a "hired gun"?

Example: Applying the Checklist

Scenario: A slip-and-fall case. The plaintiff's expert, a biomechanist, opines that the floor was unreasonably slippery.

A Good Review Would Note:

• ✅ Strength (Qualifications): Expert has a Ph.D. in biomechanics and has published on gait and slip resistance.


• ❌ Weakness (Methodology): The expert used a standard friction test, but the report fails to state the calibration of the tester or the specific environmental conditions (e.g., was the floor wet or dry?) during testing.


• ❌ Weakness (Factual Foundation): The report assumes the plaintiff was wearing dress shoes, but discovery shows the plaintiff was wearing rubber-soled sneakers. This is a critical factual error.


• ❌ Weakness (Overstated Conclusion): The conclusion states the floor "caused" the fall, but the analysis only shows the floor was "slippery." The report does not adequately rule out other causes, like the plaintiff's gait or inattention.

Final Recommendation

A high-quality expert report is a powerful tool. A poor one is a significant liability. The time invested in a meticulous, critical review is never wasted. It is the foundation for winning a Daubert challenge, preparing your expert for deposition, and ultimately, persuading the trier of fact.

Would you like to delve deeper into any specific area, such as crafting a Daubert motion or preparing an expert for a deposition?