Tag Archives: Bias

How Far Can Lawyers Push to Discover Evidence of Expert Witness Bias?

The potential bias of an expert witness is not usually a ground for excluding expert testimony. Bias goes to credibility and credibility is for the jury, not the trial judge, to determine. Before an expert can be excluded for bias, the bias must generally be so obvious that a judge can say as a matter of law that the witness is an unreliable source of information.

On the other hand, the bias of a witness is always a relevant issue in a trial. Lawyers generally rely on cross-examination as a tool to expose bias. However, the maxim that lawyers should not ask a question unless they know the answer should motivate lawyers to discover evidence of bias before the expert witness takes the stand.

Financial Bias

Unless an expert witness has a personal relationship with a party or a political axe to grind, an expert’s financial incentive to give favorable testimony is usually the strongest evidence of potential bias. The extent to which claims of financial bias are likely to sway a jury depends on the facts of the case.

Juries understand that expert witnesses are paid for their time. Everyone understands that being paid to testify creates a risk that the expert will slant testimony to favor the party paying the expert’s fee. That risk is captured in the German proverb, “Whose bread I eat, his song I sing.”

When each side calls a retained expert, however, the risk that experts will be viewed as hired guns tends to offset. One study suggests that the “hired gun” perception is strongest when an expert testifies frequently and earns substantial compensation from giving expert testimony.  The study also concludes that juries are most likely to view an expert as biased when they don’t understand the expert’s testimony. 

Lawyers can minimize the “hired gun effect” by assuring that the expert’s testimony is easy for the jury to comprehend. When juries think that an expert is making sense, they are less likely to dismiss expert testimony as the product of bias.

Discovery of Financial Bias

The Federal Rules of Civil Procedure require retained experts to disclose the amount of compensation they are being paid for their services “in the case.” A closer question is the extent to which a party can discover compensation paid to an expert, either by the same or a different party, in other cases.

Courts often draw a distinction between discovery of a party’s financial relationship with an expert and an expert’s income from broader employment as an expert witness. The issue has frequently arisen in cases involving independent medical examinations (IMEs) performed by doctors who are hired repeatedly by insurance companies. A jury might view a doctor’s substantial income from repeated testimony for the same insurance company as evidence that the doctor can be counted on to favor that insurance company. Allowing broad discovery of an expert’s income, however, arguably has a chilling effect on the willingness of professionals to act as experts.

Courts have attempted to balance an expert’s right to financial privacy against a party’s right to discover evidence of bias. An Arizona court, for example, concluded that it was inappropriate to use a subpoena duces tecum to obtain financial records before taking the deposition of a medical expert who performed an IME for an insurance company. The court viewed the “exhaustive” request for production of financial records, including tax returns, as unduly burdensome, at least as an “opening salvo” in discovery. The court concluded that the plaintiff’s lawyers should first pursue less intrusive avenues of discovery that might produce bias-related evidence.

A leading decision in Florida followed a similar analysis. The appellate court allowed a defense physician to be questioned about compensation paid for testimony in the plaintiff’s case. The court decided that a lawyer may also ask a defense expert who performs IMEs about the percentage of his or her income that was earned from testifying as an expert and the percentage earned from treating patients. Lawyers in Florida can ask for an approximation of the time the expert spends working as an expert witness, but cannot ask how much income the expert earns, either from all sources or from work as an expert witness. Another Florida decision gave lawyers greater latitude to inquire about historical income earned from the party in a case, as opposed to income earned from all work as an expert witness.

When courts limit discovery to relatively vague information offered during depositions (such as the percentage of time the witness devotes to work as an expert), whether the witness answers those questions truthfully can be difficult to determine in the absence of financial document discovery. The Arizona court offered a partial remedy to that problem by suggesting that financial document discovery might be appropriate when an expert is evasive, uncooperative, or untruthful. How parties can determine that answers are untruthful in the absence of financial document discovery is unclear.

Other courts take a more liberal approach to discovery. The Pennsylvania Supreme Court permitted interrogatories seeking discovery of all expert income earned each year during the past three years. A Kentucky court held that doctors who testify for insurance companies can be asked about the total amount of income they earn from performing IMEs. A Tennessee court agreed with courts “that have allowed expert witnesses to be questioned about the amount of income they earn from their forensic activities.” That court upheld a judge’s order for discovery of financial documents that would be filed under seal with the trial court to permit the judge to determine whether a recalcitrant doctor’s deposition testimony about his income was truthful.

Discovering financial information that might suggest the bias of a testifying expert is easier in some states than in others. Lawyers need to have a firm grasp of relevant court decisions in the jurisdiction that hears the case before they make a plan to uncover evidence of an expert’s potential financial bias.

Courtroom

Screening Experts for Conflicts of Interest and Bias

Lawyers must consider several factors when they choose an expert witness. The expert’s qualifications, reputation, and ability to communicate effectively are key considerations. The expert’s location and the lawyer’s budget are practical issues.

The potential for a conflict of interest is a factor that lawyers tend to forget. Fortunately, actual conflicts are rare. Experts are also challenged when they allegedly show a clear bias for the party that hired them. While those challenges are not usually successful, lawyers need to think about the issue of bias before retaining an expert witness.

Courts are reluctant to disqualify experts based on perceived conflicts or claims of bias. Courts tend to view those issues as going to credibility rather than admissibility. 

Even if a potential conflict does not bar an expert from testifying, lawyers want to hire credible experts. Lawyers need to consider possible challenges to an expert’s credibility based on perceived conflicts or allegations of bias. Screening experts for conflicts and bias should therefore be part of the lawyer’s assessment of potential experts.

Prior Work for an Adverse Party

Courts have the power to exclude an expert’s testimony when the expert has provided services to the opposing party. Courts exercise their power to bar the testimony of an expert who has “switched sides” when they deem it necessary “to protect the integrity of the adversary process, protect privileges that otherwise may be breached, and promote public confidence in the legal system.” 

Whether the expert will be disqualified generally depends on whether the expert received confidential information from the party that is relevant to the current lawsuit. A lawyer’s mental impression of the strengths and weaknesses of relevant claims against that lawyer’s client is an example of confidential information.

When there is a dispute about the expert’s receipt of confidential information, courts ask whether it was reasonable for the adverse party to believe that it had entered into a confidential relationship with the expert. If so, they examine the evidence to decide whether confidential information was actually shared with the expert.

Lawyers need to balance the risk of conflict against the reality that hiring an expert who was once retained by the opposing party may be advantageous. An expert’s willingness to work for both sides might be seen as evidence of the expert’s impartiality. Of course, it might also be seen as evidence that the expert is a “hired gun,” but that is a challenge facing every retained expert in every case.

When an expert has worked for the adverse party, lawyers nevertheless need to be wary. There is always a risk that the opposing party will claim that it shared confidential information with the expert. A lawyer will need to explore the expert’s relationship with the opposing party in detail and will need to assess the risk that the expert might be disqualified. If that risk is significant, the lawyer should consider whether conflict-free experts with similar qualifications are available.

The screening process should start by asking the expert whether she has any past experience with the adverse party or its lawyers. Conducting an online search for cases in which the expert testified will provide at least partial confirmation that the expert has no conflict. Still, since experts do not always testify and since it is difficult to learn of past employment as consulting experts, it is important to have a candid conversation with a potential expert witness about any contact the expert has had with an opposing party, even if the expert did not testify for that party.

Bias

Bias is often alleged by an opposing party. An expert’s consistent employment by a particular industry or group of litigants might give rise to claims of bias, but those claims are attacks on credibility that juries should resolve.

Bias may also be reflected in unreliable methodologies or a selective application of facts. Courts might disqualify experts for bias indirectly by applying the Daubert standard more strictly when there is evidence that bias may have affected the reliability of an expert’s conclusions.

Some courts have suggested that experts who base opinions on experiments or research done outside the context of litigation are more likely to produce reliable results than experts who are hired by a particular industry or group to form opinions that are specific to a lawsuit. After Daubert was remanded to the Ninth Circuit, Judge Kozinski wrote that “experts whose findings flow from existing research are less likely to have been biased toward a particular conclusion by the promise of remuneration; when an expert prepares reports and findings before being hired as a witness, that record will limit the degree to which he can tailor his testimony to serve a party’s interests.” 

That line of thought suggests that courts might be more inclined to exclude experts when they have not conducted research or expressed opinions about a particular subject before they are hired to present expert testimony. Selecting an expert who has researched a scientific question outside the context of litigation might therefore avoid claims of bias.

Still, the fact that an expert has not conducted research prior to being retained does not mean that the expert’s methodology will be tainted by bias. Courts are more likely to be troubled when, for example, an expert prepares peer-reviewed writings and fails to disclose “her potential bias because of her direct involvement in litigation in the . . . cases on which she reported.” 

Experts may also demonstrate bias when they prepare reports that contradict prior writings or testimony given in other cases if the contradictions cannot be explained by the differing facts that the expert considered. To screen against potential claims of bias, lawyers should always review an expert’s past writings and testimony to determine whether it might conflict with opinions the expert will be asked to express.