Experts. One might say that lawyers ‘can’t live them and can’t live without them.’ Experts are often key (or deemed key) to an effective trial strategy; experts can be the key to a correct adjudication or the cause of a miscarriage of justice; and they can bedevil advocates either by their deft maneuvering or clumsy and inartful presentation.
There is so much to know.
Know the numbers: Experts proliferate. A 2013 study of more than 4,000 cases from several jurisdictions found that forensic evidence was collected in 47% of criminal cases and concluded that “forensic evidence played a consistent and robust role in case-processing decisions across the jurisdictions included in the study.” Peterson et al., Effect of Forensic Evidence on Criminal Justice Case Processing, Journal of Forensic Sciences, Vol. 58, pp. S78–S90 at S89 (2013). There is no reason to think this prevalence has diminished. And the prominence of expert testimony in civil litigation is beyond question. Studies show expert participation in between 63 and 86 percent of such cases, depending on the year and the jurisdiction surveyed.
Know the law: There are a number of fundamental precepts involved in presenting and confronting expert testimony. The first, not the subject of this white paper, is mastery of the law of experts, a topic that goes beyond Daubert, Frye and the expert witness evidence rules to include discovery, ethics, and issues of privileged communication.
Know your responsibilities: Beyond but also as part of assessing whether the case will benefit from expert testimony, counsel must gain some subject matter knowledge. Sadly, the world of lawyers is populated in large part by people with no scientific or technical knowledge and often with little exposure to or awareness of the limits of a particular discipline’s methodology or validity. Read a book, go to a seminar, or hire a graduate student for a tutorial.
Know about biases: It is not enough (and indeed does not scratch the surface) to know that a witness tends to or always testifies for one side or how much they are being paid. Biases come into play at many levels – the allegiance bias that colors judgment merely by knowing what side/party hired the expert; the biasing effect of information ‘fed’ to the expert, information often irrelevant to the analysis but capable of distorting perception, choice of investigative paths, and judgment; and the biases of race and gender and class and how they may contribute to unreliable assessment.
Know the expert: The curriculum vitae is the starting place, never the end. Experts are people too – they have criminal records; acts of deception/dishonesty that may permit character attacks on their credibility; a disciplinary record or a loss or lack of licensure; prior testimony, writings or talks that may contradict their stance in your case; and an abundance of personal or business problems that may have distracted from their attention to your case.
A deep dive into expert publications and credentials is essential. It may appear impressive that the witness is a member or even diplomate of certain organizations, until you research and determine how easy it is to join such a group or attain that status. And don’t be cowed by high scores on proficiency tests – the periodic examination of an expert’s skills – until you know how stringent or easy that test is.
Know science: Unless you keep up with developments in science – problems of fraud in research articles, the reproducibility crisis where contentions or ‘findings’ in one highly publicized article are shown to not be reproducible when other researchers try the same methodology, new studies showing flaws in or limits of previously deemed reliable techniques – you can’t be prepared to assess the claims in your case.
Knowing the science also means knowing how other disciplines view your expert’s field and whether they have called its underpinnings into question.
Know their language: Lawyers must learn the lexicon of experts for two reasons – to grasp what the expert can and can’t tell us, and to discern what terms need translating for juror [and judge] comprehension. The ultimate task is to rid the expert of their terminology and make them an audience-friendly teacher and guide.
Know the audience: Is your expert’s specialty one that jurors in your community are skeptical of or warmly embrace? Voir dire must be utilized to both test for these perceptions and begin to tell the expert’s story and prime the audience for acceptance and trust. And for at least some areas of expert testimony, recognize that jurors value experts more when they substantiate law witnesses accounts and observations – an expert on whether a person has a disability is more believable when their testimony confirms what those who live and work with that individual see and experience.
Know how to entice and marvel: There is a second way to know the audience, and that is to design the expert presentation to make the jurors feel as if they learned something new, something they will want to share with others and embrace. Expose them to the wonders of the cosmos, large or small.
All this and more are necessary but not sufficient aspects of expert witness preparation and presentation. But at the end of the day experts are part of the trial narrative – one of credibility or incredulity.