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Pretrial Gatekeeping: How to Handle Junk Science and Unqualified Experts

Hon. Roy Ferguson

Pretrial Gatekeeping: How to Handle Junk Science and Unqualified Experts
RichVintage via iStock

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Aaron Rodgers, the quarterback for the Green Bay Packers, is an expert. As a Superbowl champion and four-time league MVP, he is inarguably one of the best quarterbacks in NFL history. He has skill, experience, training, and knowledge far beyond all but a handful of people in the world. In this way, he is truly exceptional. And in any courtroom in the United States, he would be permitted to testify as an expert witness on professional football. He would speak with absolute confidence in his opinions—and justifiably so.

What he is not is an astronaut. Or a brain surgeon. Or a nuclear technician. Or an immunologist.

“Dammit, Jim. I’m a Doctor, Not a Rocket Scientist!”

Public figures who are truly great at one thing often exude the same level of confidence in their opinions in other areas of great complexity—for example, geopolitics, economics, child psychology, medicine, and science. Actors frequently grandstand on social media about complex matters outside their profession that take decades of dedication to master. According to a 2006 study, many celebrities exhibit narcissistic tendencies, including superiority, authority, and overconfidence. Another study concludes that entertainers have the third-highest percentage of narcissists among their ranks of any profession. So do professors (the most), politicians (5th most), and—yes—professional athletes (6th most). It may be a manifestation of narcissism that a person who is great at one thing believes that they are equally great at all things. I don’t know . . . I’m no expert. But unlike Dr. McCoy in Star Trek, who admitted to his narrow field of expertise (“Dammit, Jim. I’m a doctor, not a rocket scientist!”), lacking expertise in 2022 does not impede claiming it.

Self-proclaimed experts are all over social media, insisting that they “did their own research.” (Usually referring to a 30-second scan of Google search results.) However, these are people who need to hear expert testimony, not ones who should be giving it. That’s where Daubert—the 1993 United States Supreme Court case that formalized “Stay in your lane” comes into play.

Junk Science and Unqualified Experts

Expert opinions can significantly impact jury decisions. Jurors often defer to experts on complicated or unusual issues. Unfortunately, even an unqualified opinion stated with confidence may sway a jury. To minimize this risk, judges act as preliminary “gatekeepers,” excluding junk science and unqualified experts. We ensure that the testimony is reliable and well-founded and that the witness on the stand is the right person to give it. It also applies to “soft sciences” and nonscientific testimony, where the witness’s expertise may be entirely experiential. (“What’s your basis for that expert opinion?” “Trust me! I’ve seen it a thousand times.”) Nonscientific experts are likely to state all opinions with equal levels of confidence, whether within their expertise or not. Cable installers may unexpectedly opine about the long-term medical risks of electric shock or schoolteachers on juvenile psychology. Or—yes—NFL quarterbacks on virology and immunology. The pretrial gatekeeping process ensures that only opinions based on the actual expertise of the witness are admitted—keeping out things they gleaned “doing their own research.”

You Can’t “Unring the Bell”

The gatekeeping process should not be given short shrift, even if funds are limited. Once the jury has heard something, the damage is often done, even if they are instructed to disregard it. “You can’t unring the bell.” Trials are won and lost on this issue alone, so behave as if your case depends on itScrutinize expert reports and determine whether each specific opinion falls within the witness’s true area of expertise. Request a gatekeeping hearing. Dive deeply into their education, experience, and training. Make them state every opinion they formed. At trial, try to prevent the global finding of, “She’s an expert.” Instead, pin them down and squeeze them in. Push for a limited finding identifying a specific area of expertise, and then object to any stated question or opinion that strays outside of that narrow focus. Keep them “in their lane.” And if you can, make that lane as narrow as the passing window on an NFL crossing pattern.

Keep Experts “In Their Lane”

Aaron Rodgers is a professional football player, not a scientist. No court would question his expertise on the former, and no court should accept his expertise on the latter. Just because someone is an expert in one thing doesn’t mean they are an expert in everything. It is your job, through the gatekeeping process, to keep experts in their lane.