Rule 702 After 2023: What It Means for Maritime Experts

Maritime experts are mostly experience experts. We did not run lab tests or publish peer-reviewed studies. We stood watches, handled ships, supervised crews, and read the same regulations and industry references the vessel owner was supposed to follow. That kind of expertise is admissible, but it has to be presented carefully, and the 2023 amendment to Federal Rule of Evidence 702 raised the stakes.

This is a practical summary from the witness side, not legal advice. Counsel should check how courts in their district are applying the amended rule.

What changed in 2023

The amendment took effect on December 1, 2023. It made two things explicit.

First, the party offering the expert has to show the court that it is more likely than not that the testimony meets each requirement of the rule: the expertise will help the jury, the testimony rests on sufficient facts or data, it comes from reliable principles and methods, and the expert's opinion reflects a reliable application of those methods to the facts of the case.

Second, the last requirement was reworded to focus on the opinion itself. The question is not only whether the expert's method is sound in general, but whether the specific opinion he offers stays within what that method can support.

The Advisory Committee's note said many courts had wrongly treated questions about the sufficiency of an expert's basis, and how he applied his method, as matters of weight for the jury rather than admissibility for the judge. The amendment was meant to correct that.

Experience still counts

None of this shuts out experience-based experts. Since Kumho Tire Co. v. Carmichael (1999), courts have applied the reliability inquiry to technical and experience-based testimony, and the Rule 702 committee note has long recognized that experience alone can qualify a witness. The point is that the expert has to explain how his experience leads to his conclusion, why that experience is a sufficient basis for the opinion, and how it was reliably applied to the facts.

"Trust me, I've been a captain for thirty years" is not a method.

What an experience-based opinion should show

A maritime opinion that holds up under the amended rule usually does several things.

• Names the standard. The specific regulation, navigation rule, industry reference, or company procedure that applied, not a general appeal to "good seamanship."
• Shows the facts. What records were reviewed, and how the timeline was built from them.
• Connects the two. Step by step, why the conduct did or did not meet the standard.
• Accounts for the other side. Addresses the facts that cut the other way rather than ignoring them.
• Stays in its lane. Opinions that drift into medicine, engineering, biomechanics, or legal conclusions are the ones courts trim most often.

The common attacks

In maritime cases, challenges tend to fall into a few familiar patterns:

• Fit: "He never served on this type of vessel." The answer is a clear explanation of how his training, duties, and the governing rules carry over, or an expert whose experience matches more closely.
• Basis: "He did not review the logs, the SMS, or the depositions." The answer is to make sure he did, and to say so in the report.
• Scope: "He is offering medical or engineering opinions." The answer is not to offer them.
• Legal conclusions: "He is telling the jury the vessel was negligent." The answer is to describe what the standard required and what happened, and leave the legal label to the court.

Advice for retaining counsel

Ask the expert, before he writes anything, which opinions he can support and which he cannot. Get the full record to him early. Read the draft as opposing counsel would. And remember that a narrower opinion that survives is worth far more than a broad one that gets struck.

About the author

Captain Mitchell S. Stoller is a Master Mariner Unlimited, former Exxon tanker master, and former Los Angeles Harbor pilot. About Captain Stoller