I have acted as a testifying expert, and I have also retained numerous expert witnesses throughout my career. A good expert is one who does her homework, who has a high degree of credibility because of her qualifications and experience, and whose opinion is based strictly on the facts. Litigation is by its very nature contentious, however, and an expert who tells it like it is may be accused of being partisan. In addition, because experts are supposed to be independent, the party hiring the expert may not be entirely pleased with the expert's conclusions. Thus, experts face potentially displeased parties on both sides of the courtroom. This article addresses the scope of expert witness immunity for statements made in the context of litigation.
Experts are different than fact witnesses because they are retained to render opinions. Defamation laws apply to misstatements of fact, but they do not apply to opinions. For this reason, defamation laws generally do not apply to expert witness testimony. In fact, until fairly recently, experts enjoyed widespread absolute immunity for litigation testimony. The reason for this judicially created absolute immunity doctrine was to protect testifying experts from retaliation.
In 1999, the Pennsylvania Supreme Court issued a decision that created a significant exception to the absolute immunity rule: experts can be held liable for negligence in the process of arriving at their opinions. LLMD of Michigan Inc. v. Jackson-Cross Co., 740 A.2d 186 (Pa. 1999). This case involved the plaintiff's damages expert. At trial, defense counsel showed that the plaintiff's expert had made an error in his $6MM damages calculation. Because this figure was based on a spreadsheet calculation that the expert had delegated to someone else in his office, he was not able to correct his testimony at trial. The judge struck his testimony in its entirety, and the plaintiff was forced to rely on other witness testimony to establish damages. The plaintiff settled the case for $750k, and the plaintiff's expert subsequently generated a corrected damages calculation of $2.7MM. The plaintiff sued its own expert for the nearly $2MM difference between this corrected damages calculation and the settlement amount.
The issue in LLMD of Michigan was whether an expert could claim absolute immunity from the party that hired him. According to the Pennsylvania Supreme Court, the answer was no. The upshot of this case is that experts are subject to malpractice claims just like the rest of us. Before accepting an engagement as an expert witness, therefore, you should carefully consider the time commitment required, whether the engagement fits squarely within the scope of your expertise, and the resources available to handle the rest of your workload during and in preparation for trial. Had the expert in LLMD not delegated the initial calculation of damages, he may have been able to correct his calculation on the stand, thereby avoiding the civil suit from his client altogether.
The scope of expert witness immunity is an issue of state law, and not all states have approached this issue similarly. Providing false testimony under oath constitutes perjury in all states, and expert witness immunity does not apply in that situation. Rather, the issue with which the court grappled in LLMD was whether and to what extent negligence--without malicious intent--is actionable. At least in Pennsylvania, the door has been opened to such suits. Since LLMD, courts in Connecticut, Louisiana, Massachusetts and West Virginia have all found exceptions to the absolutely immunity doctrine as it applies to expert witnesses.
Since LLMD, only North Dakota has unequivocally upheld absolute immunity for experts. In Riemers v. O'Halloran, 678 N.W.2d 547 (N.D. 2004), the North Dakota Supreme Court held that the threat of perjury and the fact that the expert witness was subject to cross-examination were sufficient incentives for experts to tell the truth. The court also held, however, that absolute immunity protected experts from civil suits based on knowingly providing false testimony.
O'Halloran had been appointed by the district court to calculate Riemers' income for purposes of child support payments. Riemers--representing himself pro se--claimed on appeal that O'Halloran had engaged in unprofessional, fraudulent and unethical actions. Riemers cited a "litany" of constitutional provisions and an international treaty, none of which the appellate court found to be pertinent. One cannot help but wonder whether the North Dakota Supreme Court would have come down so strongly in favor of absolute witness immunity had it been presented with a case more factually similar to LLMD--one where the expert had actually made a mistake.
