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May 04, 2022 Feature

Expert Energy: Effective Use of Experts in a Family Law Case

Steven N. Peskind

Divorce lawyers routinely use experts in both contested and uncontested family law cases. Experts enlighten us and our clients, and coach us on appropriate case strategies. Sometimes we use them forensically to investigate the facts, supporting or disputing claims. Still other times we use them to offer opinions in court. This article provides an overview of the various roles experts play in a family law case and how we can effectively use them.

Consulting Experts

There are two types of expert witnesses: those retained to testify and those retained to help us prepare our case. The first type is testifying experts and the latter is consulting experts. Unlike a testifying expert, the consulting expert is ordinarily beyond the scope of discovery. Thus, the expert’s identity, opinions, and conclusions can be kept confidential.

For example, divorce attorneys can use a consulting expert to value a piece of property without disclosing the identity of the expert. If the opinion is disappointing, the information could be pocketed, providing an opportunity to develop alternative case strategies. If the opinion is satisfactory, the consulting expert could be converted into a testifying expert (subject to disclosure) and the opinion could be used during negotiations or at trial.

Consulting experts also help lawyers prepare for depositions or trials. Effective cross examination of an adverse expert includes making the expert admit to the weaknesses in their analysis or report. A consulting expert helps identify those weaknesses and assists the lawyer to exploit them. No matter how smart we think we are, few of us have adequate skills to expose all of the chinks in the opposing expert’s armor. Having a consulting expert to help develop a cross examination is invaluable.

While unorthodox, you can also use consulting experts to identify weaknesses in your own expert’s analysis, and to bolster the report. This is a delicate enterprise because if you challenge your testifying expert with another expert, your expert’s ego may be bruised, leading to a less enthusiastic witness. For this reason, conduct the review without notifying your principal expert. If the consulting expert reveals major flaws, direct action may be necessary.

Testifying Experts

In contrast to consultants, testifying experts are those retained to investigate and render opinions in court regarding a relevant issue in the case. To do so, the testifying expert must have some specialized knowledge and be qualified to provide the opinion. Sometimes, instead of offering opinions, the expert is hired to educate the court. The Committee Comments on Federal Rules of Evidence 702 describe the role of the expert as educator : “. . . an expert on the stand may give a dissertation or exposition of scientific or other principles relevant to the case, leaving the trier of fact to apply them to the facts.” [Throughout this article, I rely on the Federal Rules of Evidence (FRE). Consult your own state law for application in your home jurisdiction.] For example, in a divorce case involving a family farm, a farmer who has substantial experience in farming could provide expert testimony on how farmers generate income from farming. Or a psychologist could give an exposition in a child relocation case on clinical studies that relate to uprooting adolescents from their home.

Unlike a consulting expert, the testifying expert is subject to full discovery. This means that their file can be subpoenaed, their opinions must typically be provided in advance of the testimony, and they can be deposed. With this in mind, be scrupulous with your communications with the expert to avoid any embarrassing disclosures (“C’mon, John, can’t you get the number up a bit . . .”).

Retaining the Expert

Whether retaining a consulting or testifying expert, formalize the relationship in writing. Identify the scope of the assignment and clarify the expectations for the expert. For example, when hiring an expert to value a business interest, provide the standard of value and the date of the valuation (“we are looking for an opinion of the fair market value of Mr. Caulfield’s 43 percent interest in Caulfield Motors as of December 31, 2000”). It can be deadly to your case if the expert uses the wrong standard of value or valuation date.

Confirm the timeline for the expert. Be specific about deadlines. Advise the expert of critical dates and ensure that they can accomplish the task within the target date. If a trial date is set, make sure the expert is notified as soon as possible so the expert can plan and potential scheduling conflicts can be avoided.

Some experts prefer that lawyers sign the engagement agreement. Some feel that the optics are better if the lawyer executes the engagement; it theoretically enhances the expert’s objectivity as the litigant is not the retaining party.

Obviously, the attorney doesn’t want to be personally obligated for the cost, and that should be spelled out in the engagement agreement, even if the attorney is the formal employer of the expert.

As addressed above, be sure to remind the expert that communications are discoverable. Admonish the expert not to put anything in writing that could be fodder for impeachment. If the expert has concerns about the assignment, or any other negative insights about the task, advise the expert to share those comments in person, or by phone rather than by e-mail.

Qualifying the Expert to Testify

When offering the testimony of an expert at trial, you must first establish that the subject matter of the testimony relates to some specialized knowledge and that the expert possesses sufficient skill to reliably testify. The subject matter of the testimony must be within this particular witness’s specialized knowledge and beyond the knowledge of a layperson. Specifically, FRE 702 provides that an expert may testify if “the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue. . . .” The expert’s testimony is not limited to scientific or technical matters; an expert may testify if it can be shown that the expert has any specialized knowledge that will assist the trial court.

The Scope of the Assignment

The scope of the expert’s assignment is often described in syllogistic terms. The general theory or principle underlying the expert’s report is called the major premise. The minor premise is the case-specific information upon which the expert relies. When the facts of the case are applied to the theory, it results in the expert’s ultimate conclusion.

While ordinarily experts in family law cases provide opinions regarding valuation of assets or opine on child-related matters, sometimes their opinions rely on novel scientific theories. For example, an expert may be offered to opine on a new method of identifying or diagnosing parental alienation. When that occurs, you must qualify both the validity of the major premise (the science behind the analysis) as well as the propriety of the data relied on as applied to that science.

Frye v. United States

The first case to explore the reliability of scientific evidence was Frye v. United States, 293 F. 1013 (D.C. Cir. 1923). In Frye, the U.S. Court of Appeals for the D.C. Circuit articulated a standard for admission of scientific testimony: whether the proposed theory is generally accepted in the scientific community. The Frye standard requires consensus in the scientific community as a yardstick to measure the reliability of the scientific evidence. Only those methodologies considered reliable by the general scientific community were deemed acceptable. In the 1970s, the Frye standard came under attack. Critics complained that Frye precluded cutting-edge scientific evidence, too new to be recognized by the scientific community at large. This criticism culminated in FRE 702, which rejected Frye’s “general acceptance” theory in favor of a general reliability standard.

Daubert v. Merrell Dow Pharmaceuticals, Inc.

In Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), the US Supreme Court held that the Federal Rules supplanted Frye’s general acceptance standard. The high court held that the proponent of scientific evidence must first establish that the expert’s technique is scientifically reliable by establishing that the expert’s hypothesis is empirically valid. To evaluate the validity of the hypothesis, the trial judge should consider the following:

  • Whether the proposition is testable and has been tested;
  • Whether the proposition has been subjected to peer review and publication;
  • Whether the methodology has a known error rate;
  • Whether there are standards for using the methodology; and
  • Whether the methodology is generally accepted.

Some states continue to use the Frye test (substantial acceptance) to evaluate controversial expert evidence. Other states follow Daubert, which requires a balancing test of various factors to determine reliability of the testimony. It is important to know what standard your jurisdiction uses and apply that standard when seeking admission or challenging an expert’s testimony as to a particular subject matter.

A Frye/Daubert Hearing

In order to gauge the reliability of controversial expert testimony, the court may conduct a preliminary hearing. At that hearing, the parties present evidence concerning the validity of the expert’s major premise. Other experts may be called to support or refute the theories to be relied upon in the case before the court. If the court determines that the expert’s major premise is unreliable, the expert’s testimony is inadmissible. If not, the court will allow the expert to testify, subject to any other challenges regarding the expert’s conclusions (minor premise). For example, the expert’s application of the scientifically reliable technique may have been flawed or the expert may have drawn incorrect conclusions from the data.

Reliability of Nonscientific Expert Testimony (Kumho Tire)

Expert testimony is not limited to scientific opinions. For example, a business valuation, for example, involves an expert with specialized knowledge, but the expertise is not “scientific” in nature. The Supreme Court responded to this issue in Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999). In Kumho, the Court held that while the Daubert factors remain valid for scientific evidence, nonscientific testimony must be scrutinized differently. The trial judge may consider any pertinent Daubert factors and disregard those that are inapplicable. FRE 702, in its present form, codifies the Kumho decision by granting the trial judge discretion to determine whether “the expert has reliably applied the principles and methods to the facts of the case.”

Foundations for Expert Testimony

Regardless of the nature of the expert testimony, a foundation is necessary before an expert may testify. In a routine case, where no novel scientific theories are being put forth (the vast majority of our cases), a Frye/Daubert analysis is unnecessary. Regardless, you still must lay a proper foundation to confirm the expertise of the witness. Often this is unnecessary due to the court’s familiarity with the witness (allowing the court to take judicial notice of the expert’s qualifications). But in a case where the judge is unfamiliar with the witness or the nature of the testimony, you must lay a formal foundation.

Laying the foundation for an expert, particularly one with extraordinary credentials, is an opportunity to enhance the expert’s credibility. For example, assume you want to offer the opinions of a clinical psychologist who is nationally recognized as an expert on child development. The expert is being called to testify to the parties’ respective parenting styles and how they impact the children. Assume the counter-expert is a local therapist who has been licensed for only a year. The act of laying the foundation for the testimony allows the expert to “brag” his credentials and differentiate himself from the rookie. When you have an expert of this caliber, never accept a stipulation as to the expert’s expertise and lose the opportunity to highlight the expert’s credentials.

To lay a foundation for the expert to testify, start with the expert’s curriculum vitae (CV). You should be able to lay the foundation for submission of the CV in about three questions:

  1. Mr. Paradise, I’m showing you what has been marked as petitioner’s exhibit 4. Can you identify this document? (Yes, it’s my CV.)
  2. Who prepared this document? (I did.)
  3. Is it current and complete? (Yes.)

Then, move to admit the CV so the court can review it while you examine the witness on the high points in the document, for example, “I see you obtained your PhD at the University of Chicago. What was the subject matter of your dissertation?” Common information to elicit when qualifying the expert includes:

  • Degrees from educational institutions;
  • Specialized training in this field of expertise;
  • Licenses or certifications in the field;
  • Professional experience;
  • Teaching experience;
  • Relevant publications;
  • Membership in professional organizations; and
  • Prior expert testimony.

Highlight those credentials most important to the assignment. We don’t care whether the expert was an Eagle Scout. We do care, however, that he has 20 years of clinical experience and was the keynote speaker to the AFCC on child custody.

After laying the foundation, tender the expert to the court, “May it please the court, I tender Sal Paradise as an expert in child psychology.” The adverse party has the right then to challenge the expertise of the expert and may examine by asking questions about the expert’s credentials. This process is known as “voir dire” of the witness. If the judge deems the expert unqualified, the testimony and report are barred. Voir dire questions might include questions on the following topics:

  • Lack of education of the expert;
  • Deficient training;
  • Lack of skill in implementing any objective testing;
  • Whether the testimony does or doesn’t involve specialized knowledge;
  • Lack of adequate information (e.g., meets only one party and intends to render an opinion regarding placement of a child);
  • Reliance on improper facts, test procedures, or legal principles (e.g., the expert intends to offer an opinion about custody based upon the tender year’s doctrine when the law disallows the court from considering the doctrine).

If the judge allows the expert, the party offering the expert may then proceed to elicit the expert’s testimony. The opposing party has the opportunity to fully cross-examine the expert at the conclusion of the direct examination.

The Factual Basis of the Expert’s Testimony

Ordinarily the expert is retained to render an opinion, but not always. The expert could testify to research or other data and leave it to the trial court to apply the research to the facts of the case. Either way, during their testimony, the expert needs to provide the underlying basis of their analysis, referred to above as the minor premise of the report. What did they consider? What information did they review as part of their investigation? FRE 703 controls the nature of this testimony:

An expert may base an opinion on facts or data in the case that the expert has been made aware of or personally observed. If experts in the particular field would reasonably rely on those kinds of facts or data in forming an opinion on the subject, they need not be admissible for the opinion to be admitted.

There are three factual sources for the expert’s opinion. The first is facts the expert personally knows. Examples include a custody evaluator’s interviews and a business valuator’s site visit where they observed the operations of the business.

The second factual basis for the expert’s opinion includes hearsay statements from third parties. FRE 703 specifically allows an expert to rely on hearsay “[i]f experts in the particular field would reasonably rely on those kinds of facts or data in forming an opinion on the subject . . .” The trial judge maintains discretion to determine whether the expert’s reliance on the hearsay information was reasonable under the circumstances. Deference to the specialty’s use of this information is the general rule. If the court ultimately believes the expert’s reliance on hearsay was improper, the court can disregard the expert’s opinion.

The final factual basis of the expert’s opinion is assumed facts. Under some circumstances, the expert does not personally do an investigation but may nevertheless testify and render an opinion based upon assumed facts. Assumed facts are presented in a hypothetical question, and the expert may testify based upon those assumed facts. A party may use a hypothetical question on direct examination as well as on cross-examination of the opposing expert. On cross, the questioner may ask the opposing expert a question based upon certain alternative facts they want the expert to assume. For example, “Mr. Jones, assuming the capital expenditure adjustment was $40,000 instead of the $20,000 figure you relied upon, all things being equal, how would that affect the value of the business?”

The Expert’s Opinion

To recap, before the expert can testify, the proponent of expert testimony must lay a foundation for the following:

  • The propriety of the subject matter of the report and testimony;
  • The qualifications of the expert;
  • The reliability of the theory being used (major premise); and
  • The factual bases of the expert’s opinion (minor premise).

Assuming an examiner meets the foregoing, the expert will be qualified to render their opinion. Many jurisdictions require the expert to cloak the opinion as being based upon “a reasonable degree of certainty.” The Federal Rules of Evidence don’t. Consult your state law to determine the proper foundational language for eliciting the opinion of an expert.

FRE 704 allows expert testimony concerning the ultimate issue. For example, the expert may testify to the best interest of the children and recommend a particular custodial arrangement. FRE 705 provides that the expert may give their opinion on direct examination without providing all of the underlying facts or data relied upon in reaching the conclusion. The rule essentially shifts the burden to the cross-examiner to elicit facts the expert relied upon. This rule avoids the necessity of a lengthy recitation of information prior to the expert rendering the opinion. In practice, however, it is rarely effective for an expert to disclose the facts for the first time during an adverse examination. The facts should be revealed during direct examination to create a more persuasive presentation. While the rule doesn’t require it, common sense dictates that experts must explain their opinions for maximum impact.

Court-Appointed Experts

Most jurisdictions allow a trial court to seek its own independent evaluation of the best interests of children. Some states allow a trial court to appoint its own financial expert to serve as a friend of the court. FRE 706 codifies the rules pertaining to court-appointed experts. This rule authorizes a trial judge to appoint its own expert, either one agreed upon by the parties or one chosen by the judge. Compensation and other terms are specified in the rule. Ordinarily, neither party is prohibited from hiring their own expert. However, the advisory committee notes state: “The ever-present possibility that the judge may appoint an expert in a given case must inevitably exert a sobering effect on the expert witness of a party and upon the person utilizing his service.”

Assuming the court does appoint its own expert, that expert would typically prepare a report and tender it to both parties for review. Depending upon the jurisdiction, the report may be automatically admissible as the court’s exhibit, subject to either party calling the expert for cross-examination. From a tactical perspective, remember this is the court’s hand-chosen witness. The lawyer must behave accordingly and treat the court’s witness with proper respect. Also, local rules or procedure may limit either lawyer’s ability to contact or discuss information with the court’s expert. Do not violate any rules or protocols that will taint the report or irritate the judge.

Call in the Experts

Harness the energy of experts in your cases. Creatively employ them to help you help your clients. Think of novel ways that they can help you either as a consultant or as a testifying expert. While many fear experts because of their “expertise,” you leave money on the table for your client when you avoid them. While you may not speak the same language, you speak a language that the court will understand. Become your expert’s translator and persuasively present the testimony in a way that it moves the court in your favor.

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Steven N. Peskind of the Peskind Law Firm in St. Charles, Illinois, is a highly experienced family law practitioner, American College of Family Trial Lawyers Diplomate, and National Institute of Trial Advocacy instructor. He blogs about the practice at