Forensic Engineering Editing and Proofreading Services

Committee notes to the federal rules of evidence explain what an amendment does. The note to the 2023 amendment of Rule 702 also tells the courts that a body of their case law is wrong, and it begins the point with a contrast. "But many courts have held that the critical questions of the sufficiency of an expert's basis, and the application of the expert's methodology, are questions of weight and not admissibility."¹ The sentence that follows settles it. "These rulings are an incorrect application of Rules 702 and 104(a)."¹

What the amendment changed

The amendment was adopted on April 24, 2023 and took effect on December 1, 2023.¹ An expert may now testify "if the proponent demonstrates to the court that it is more likely than not" that four conditions are met.¹ Three of them concern the knowledge, the facts or data, and the principles and methods.¹ The fourth is that "the expert's opinion reflects a reliable application of the principles and methods to the facts of the case."¹

The committee note explains what the fourth condition is for. "Rule 702(d) has also been amended to emphasize that each expert opinion must stay within the bounds of what can be concluded from a reliable application of the expert's basis and methodology."¹ The note then bounds the inquiry from both sides. "Similarly, nothing in the amendment requires the court to nitpick an expert's opinion in order to reach a perfect expression of what the basis and methodology can support."¹ It adds that the Rule 104(a) standard "does not require perfection. On the other hand, it does not permit the expert to make claims that are unsupported by the expert's basis and methodology."¹

Courts have long described the report as a document

A footnote in a 1998 Seventh Circuit opinion collects the drafting standard. Reports "must not be sketchy, vague or preliminary in nature," the footnote says, citing the Advisory Committee note to Rule 26.² Citing a district court, it adds that reports "must include 'how' and 'why' the expert reached a particular result, not merely the expert's conclusory opinions."²

A 2022 order in the Eastern District of Washington shows what falls short. Writing about a medical expert, the court found that "Rather than explain the bases and reasoning for his opinions, Dr. McMunn has disclosed one-to-two sentence conclusions."³ The opinions were "vague as the reader must guess" what several of their own terms referred to.³

An order applying the amended rule to an engineer

In March 2026 the District of Oregon excluded the opinions of a metallurgical engineer who had examined a failed nylon pull-strap on a trailer roll-up door. "The Court concludes on this record that plaintiff has not established by a preponderance of the evidence that Marksthaler's opinions are based on adequate facts or data or on a reliable methodology."⁴ Quoting an earlier decision, the order also describes what a second report may not do. "[A] rebuttal report is not the time to change methodologies to account for noted deficiencies; instead, it is to respond to criticisms of such methodologies."⁴

The report has a fixed content list, and drafts do not

Federal Rule of Civil Procedure 26(a)(2)(B) requires "a complete statement of all opinions the witness will express and the basis and reasons for them."⁵ It separately requires "the facts or data considered by the witness in forming them."⁵ The rule says considered there and relied on elsewhere, and choosing between them is a drafting decision.⁵

Drafts are treated differently. Rule 26(b)(4)(B) protects "drafts of any report or disclosure required under Rule 26(a)(2), regardless of the form in which the draft is recorded."⁵ Rule 26(b)(4)(C) protects communications between a party's attorney and a reporting expert, subject to three exceptions.⁵ How those rules apply to a given engagement is a question for the lawyers on the case.

What an editor works on, and what the engineer keeps

No editor forms an engineering opinion, chooses a method, or decides whether a conclusion follows from an analysis. Those acts belong to the engineer who signs the report, and we neither review them nor adjust them. For engineers licensed in Texas, board rules reach engineering work that does not bear a seal. That work, "including but not limited to research reports, opinions, recommendations, evaluations, addenda, documents produced for litigation," must carry the engineer's printed name, date, signature, and the P.E. designation.⁶

Everything written around that signature is still text. We check that every opinion stated in a summary also appears in the body, worded the same way, and that the facts and data considered are listed rather than described in general terms. We follow a term from the scope section to the conclusions and report where its meaning shifts, and that a figure in the text matches the figure in the appendix. We check that a qualifier attached to a measurement is still attached in the sentence that relies on it. Client work is confidential, without qualification.

What a report can say is limited by what was recorded earlier. ASTM E1188 covers "the collection and preservation of information and physical items by any technical investigator."⁷ ASTM E620 says its own practice "establishes those elements of the expert's opinion report which will make the report understandable to the intended recipient."⁸ The same sentence asks that those elements "focus on the technical aspects germane to the purpose for which the opinion is rendered."⁸ Under the amended Rule 702, the judge reading that report decides whether the opinion will be heard at all.