Evaluating Your Expert Witnesses and Witnessing Their Value

TASA ID: 1646

Three friends of mine, all working expert witnesses, called me to recount their experiences with private investigators who interviewed them for prospective cases. One complained that the private investigator “asked me if I could stand up to a Daubert Hearing,” another seemed insulted that she was asked what her answer would be if the prosecutor “questioned my high expert fees,” and the third groused about being asked by the interviewing P.I. “why I prostituted myself in ‘criminal defense alley’ ”— the throng of law offices that occupied a corridor in and around the county courthouse. They accounted for more than 50% of his revenues the preceding year. All of these colleagues demanded to know (from me) what was up! Why were they being grilled like this? Were they viewed as expert witnesses or as suspects? Could P.I.’s even ask such questions? They all claimed this was a “first,” but they suspected it wouldn’t be the last time they’d be so queried. I told them that they had the right to remain silent, if they chose, though by taking that tactic; their value in the P.I.’s eyes might cascade like Niagara Falls. What shocked them; however, was my telling them that P.I.’s could ask such questions—and that more P.I.’s should ask those kinds of questions and many more like them!

Questioning Prospective Witnesses…a Necessity

Questioning your prospective expert witness is vital. If you’re running defense for your hiring attorney by only scanning a pile of expert witness resumes, you should probably add a vital component to your examination efforts: Call the experts into your office or at least interview them over the telephone. You and the attorney for whom you work cannot afford to have them “drilled and killed” on the witness stand by a salivating prosecutor or other opposing counsel. Expert witnesses should expect questions about Daubert whether or not they are doctors, scientists, engineers, or economists. Daubert is the “gatekeeper” standard for testing in court not whether there is evidence, but whether that evidence was gathered properly.

So, your expert witnesses can bet their next breaths that their testimony about the method for gathering evidence will now and forever be deemed light-years more important than whether there is evidence. This “method-over-matter” point of view held by courts must be understood by all expert witnesses—regardless of their discipline and expertise—as a signal to include the intellectual method they utilize to arrive at their expert opinion. And it is their responsibility to be ready to address that. Daubert, inside courts, has evolved away from being merely THE Supreme Court threshold decision about the scientifics of fingerprinting (Daubert v. Merrell Dow) to its present day “gatekeeper” evidence-controlling purpose: A Daubert Hearing alerts the expert witness that his or her thinking and reasoning about the evidence is critical to analyzing the method used for bringing that evidence into court and the light of day in the first place.

What, Who…Daubert and Me?

Don’t let your prospective expert witnesses cop out by telling you, “Daubert doesn’t apply to me. I’m not a medical doctor/engineer/scientist/economist.” Daubert, if nothing else, scrutinizes for due diligence in the evidentiary thinking processes of non-scientific pre-testimony expert witnesses. Daubert can either seat expert witnesses or strike them and send them packing. You can even advise prospective experts on some of the Daubert-type questions opposing counsel might ask them, to try to disqualify them: The theory or technique you’ve described, has it been tested and validated? This kind of question goes to the issue of how established, experienced, and even respected your expert witness is. Your attorney is paying him or her for their expert opinion; opposing counsel is not paying them a dime. Therefore, the big, imaginary “zero” opposing counsel sees on the expert’s forehead represents a target at which to aim and fire the toughest questions.

The responses your expert gives should be precise, non-argumentative, and without any arrogance or aggrandizement. He or she should sound as though they are well-experienced and, as appropriate, cite other sources in their profession who validate their opinion. What about peer review? Has your theory or technique been peer-reviewed and published? This question goes to whether and how your expert is perceived and regarded by his or her peers in their field of expertise: Is he or she known or unknown? Highly-regarded or an “also-ran?” Credible or discredited? Peer reviews are considered the litmus test. Your expert should frankly—without boasting—define and describe those of his or her theories that have been peer-reviewed and published. What is the potential or previously documented rate of error of the method used? This question goes to the reliability of your expert’s theory. It is important to remember that a high error rate does not always mean the theory is unreliable; it merely means that the rate of error is something to factor in, not disregard. A significant error rate does not render invalid your expert’s theory. By the same token, if your expert’s theories or techniques are controversial, that is not necessarily a negative against your expert. Controversy is active and ongoing debate; it doesn’t mean your expert’s work and reputation are tarnished. Since opposing counsels often look for opportunities to do a verbal “Assault-and-Daubert,” you can tailor-make your own questions to acquaint your expert with and prepare him or her for Daubert issues.

Questions Are Critical—They Aren’t Criticism

Expert witnesses should not be put off or feel insulted about any questions the P.I. asks them. P.I.’s can make their interviewees feel more comfortable about answering their “twenty questions” by advising them that “I have to ask you several questions along the way. Better I do it before the prosecutor does; that way you and the attorney I work for can look good in court.” Or, “I hope you won’t be insulted, but the more questions you answer for me, the more qualified my attorney can make you look in court.” Or, “Prosecutors regularly dispute the qualifications of the expert witness. The Daubert Hearing gives them an additional tool to not only dispute but also to try to disqualify you. We wouldn’t want that to happen, would we?” With this in mind, expert witnesses should also expect to be asked questions about their “high” hourly fees. A private investigator friend of mine recalls a prosecutor grandstanding before the jury by haranguing the expert witness about his fees. He ended by telling the expert that his boss, the district attorney, “pays me only a fraction of what you make per hour.” To which the expert witness replied: “Well, the district attorney certainly knows your worth far better than I do.” The courtroom, including the judge and jury, erupted in laughter; the prosecutor, though, seemed not to be amused.

Human nature is often unpredictable, and just because an expert’s good-natured humor may incite laughter from a judge and jury, does not mean that the expert is favorably regarded at all. An embarrassed and insulted opposing counsel can often very skillfully turn a moment of levity against the expert. Indeed, the judge, while laughing and seeking to mollify opposing counsel’s bruised ego, might even discredit and dismiss the expert as off-base and impolite. That well-aimed response might—in jury deliberations—even be regarded as impertinent and rude. The jury might be ashamed of its spontaneous outburst of laughter and, with stony faces, try to rectify their “sin” by regarding the expert with mistrust…as somebody given to self-aggrandizing and discourteous responses. It is better that opposing counsel expose his or her own feelings of annoyance about your expert’s so-called “high fees” and be the spectacle in their own circus of critical questions. Your expert need not be caught up in this game. You might wish to repeatedly and diplomatically advise the expert to tell the truth, to act naturally, not to exhibit arrogance or ridicule, not to joke, and certainly not to argue with opposing counsel. In this context, “Sharp tongues sometimes cut their own throats” is a maxim that describes what could happen to either an expert witness or the opposing counsel. A backlash could hurt the expert more than it hurts opposing counsel.

It’s Preparation…Not Ping-Ponging with the Prosecution

Rather than risk your expert’s trying to match wits, in the foregoing manner, with the prosecutor, I recommend that the expert be prepared to reveal to you why their hourly fees are the way they are. There are at least nine reasons your expert witnesses might find valuable support for questioned fees: (1) years of experience in the field; (2) court certification your expert has; (3) membership on any court’s Panel of Experts; (4) rank and tenure in your expert’s professional discipline, such as college and university teaching; (5) books, papers, or journal articles your expert has published; (6) the number of cases in which your expert has provided expert testimony; (7) your expert’s membership and rank (such as president) in professional associations; (8) your expert’s participation and presentation at professional conferences, particularly those where continuing education credits (e.g., CLE) are awarded to their audiences of licensed professionals; and (9) your expert’s media profile: how often he or she has appeared on television or radio providing their opinions on national topics. Juries can often follow a logical trail and understand why a judge allows expert witnesses into the court to opine about cases. In other words, juries are not usually put off by carefully-explained and well-reasoned justifications the expert makes for his or her fees. The expert witness should never be gulled by the prosecutor’s comparison of his or her own salary with that of the expert. Tell your experts to treat their fees as a kind of evidence and to speak about them openly and frankly. Rather than be or feel vilified by the prosecutor, your experts can show themselves as vital to the case because of their fees.

Frank and Direct Answers Are Best

It is highly doubtful that a prosecutor would insinuate that an expert witness “prostitutes” himself or herself in certain financially-lucrative environs around the court. Most fish find their water in the ocean. Too, any number of expert witnesses might find prospective cases among a virtual “sea” of law offices around the courthouse. It’s only practical and makes good business sense to market themselves in and among such a constellation or cluster of law firms. What the P.I. means by the “prostitute” question (if he or she even chooses to use that word at all—however, one P.I. did when querying me!) is whether the expert witness shows a dominant bias—for either prosecution or defense—in the kinds of cases taken in, say, the past year. Again, it’s better that your prospective expert answer the question head-on and directly.

By stating the obvious—that most private law firms house only defense counsels—your expert can show he or she is merely answering legally-constituted calls for defense expert testimony support and not turning away prosecutors’ requests to provide expertise on cases. To be sure, prosecutors use expert witnesses. However, the number of cases for which they bring an expert into court is but a fraction of the frequency with which defense attorneys need and use experts. Even in those cases where the defendant has been pronounced by the court as “indigent” (impoverished and unable to pay) he or she is still the client of a defense attorney who thus may need an expert witness. There’s also the fact that prosecutors select their expert witnesses from the court’s approved Panel of Experts. If your expert witness is not on the panel, that may not be his or her fault. Thus, their answer to an inquiring prosecutor, regarding the percentage of prosecution and defense cases on which they’ve worked, can reasonably be: “I would probably work more prosecution cases if I were on the court’s Panel of Experts, but I am not; and thus far I’ve not been chosen by the district attorney to participate on a case.”

 If your expert has completed the application process to be on the panel, he or she should certainly state that; that fact is good public relations. The prosecutor knows that an expert’s not being on the court’s Panel of Experts may have little or nothing to do with the expertise and qualifications of the expert. Often, the court’s panel is full and there simply is no room for another expert. Frequently, not all of the judges, or any single one of them, who comprise the team that chooses expert witnesses for the Panel of Experts, hears cases for which a given expert’s rare experience and expertise are needed. The court’s “problem” here is, of course, known by the prosecutor, and is not something to be held against the expert. Your expert is not responsible for any past or present circumstances inherent in the court. Again, if your expert witness has made application to the court, to be on its Panel of Experts, he or she should so state. That revelation can clear the air and deflect any “end run” the prosecutor might try to make in the effort to disqualify your expert.

Who Can Pre-qualify Your Experts Better Than You?

Both P.I.’s and expert witnesses provide a huge and valuable service to the attorneys who employ them. And every P.I. and attorney I’ve worked for has been highly appreciative. Expert witnesses should regard questions from P.I.’s as appropriate and necessary safeguards to protect the legal rights and interests of the client and fulfill the case objectives of the hiring attorney. As a Private Investigator, you know which way the winds inside the court blow (or are likely to) better than any roomful of expert witnesses. Take time to ask your prospective expert witness the hard questions, and to pose the tough issues. If possible, meet and confer with him or her personally. Go over their resume and interview them about the information it contains. Ask them to tell you about their four cases (“your top four”) that are unique and unlike any others on which they’ve worked; then ask them to define what makes these four cases stand apart from the rest. Show them a calendar, and ask them about their availability for trial as you highlight the anticipated trial dates. Determine whether they might have schedule conflicts.  

Taking Time to Talk Now Increases Value Later

By taking the time to have at least a one-hour “sit down” discussion with any prospective expert, you can pre-qualify him or her for your attorney. Your prospective expert’s opinion is the purpose for which he or she might be hired, and it ought to be the rock-solid foundation upon which their role and reputation are established and respected by the court. Therefore, you’re reviewing and clarifying the opinions to which they will be testifying to, is critical. It will do you both good to hear, in their own words, what opinions they hold about the case and what they will likely say in court. Equally important, their going over with you the facts and assumptions that frame the bases of their opinions is a practical step; it is the productive equivalent of a baseball player doing warm-up calisthenics and taking batting practice. One can never review one’s facts and assumptions too much or too often; such review prevents one from being caught off guard, in “the blind” by opposing counsel’s peppering questions.

You will need to hear and your prospective expert needs to say how, that is, in what way they derived their opinion: What methodology did they employ? This tracking the trail from beginning to end sets up a logical step-wise chronology that can be as impressive as it can be instructive. In my own experience, prosecutors have sometimes been left astonished and speechless before admitting, “No further questions, your honor,” to the judge, after I have carefully laid out the methodology that framed and informed my professional opinion. You will certainly want to ask your expert when his or her opinion was formed. You can stress the importance of their addressing the timing of the formulation of their opinion, as the opposing counsel will seek to find some kind of fault with the timing—holding it up to be premature or incomplete, and the resultant opinion as inaccurate.

Your thorough and intensive interviews and evaluations of expert witnesses can result in your attorney’s being able to witness their value in court.


The expert teaches law in the Police Sciences curriculum at El Camino Community College, California’s largest community college. He is a member of the Panel of Experts of the Los Angeles Superior Court, Foltz Criminal Justice Center. He is an Expert Witness who enjoys a large media profile on NBC, CNN, CBS, ABC, and FOX News, as a result of his nationally-acclaimed book, Jack and Jill, Why They Kill, used in colleges and universities nationwide. A Superior Court-certified expert, his expertise is in Gangs; Street Terrorism; School Safety; and Juvenile Violence/Personal Injury. He works nationwide and has provided opinion and testimony in a federal court gang bank heist cast; a U.S. Navy court-martial gang case; a triple murder death penalty gang case; a prison parolee school assault case; weapons cases; and numerous school safety personal injury and gang-related cases. He was one of the keynote speakers at the Columbine High School memorial ceremonies honoring the slain students. He is also the author of a violence prevention and education curriculum, B.R.A.V.E. (“Be Resilient Avoid Violence Everywhere”) and a member of the American Academy of Forensic Sciences. 


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