ARTICLE: Limitations on Cross-Examination of Lay and Expert Witnesses

Civil Litigation  

Limitations on Cross-Examination of Lay and Expert Witnesses

By Daniel E. Cummins, Pennsylvania Law Weekly
May 19, 2015
  
Editor's note: The author served as defense counsel in Detrick v. Burrus.

It is well settled that "the purpose of ... civil trials is to discover the truth" of the claims and defenses presented by the parties, as the court held in Bailey v. Tucker, 621 A.2d 108, 113 (Pa. 1993). It is equally well settled that, in the search for the truth at trial, it is for the jury to determine the credibility of the witnesses, including expert witnesses, along with the weight to be given to the testimony of any witness presented, as in Ludmer v. Nernberg, 640 A.2d 939, 942 (Pa. Super. 1994).

The most important tool provided to a litigant to test the credibility of parties, witnesses and expert witnesses at trial, and thereby challenge the truth of the adversary's claims, is the right to conduct a thorough and cutting cross-examination.

Given the adversarial nature of trials, issues often arise pertaining to the extent to which a witness can be cross-examined. Recent cases reviewed below confirm that there are indeed some limits to efforts to attack the credibility of both lay and expert witnesses at trial.

Scope of Cross-Examination Not Unlimited

Pennsylvania Rule of Evidence 607(b) provides the general rule that "the credibility of a witness may be impeached by any evidence relevant to that issue, except as otherwise provided by statute or these rules."

Two recent court decisions illustrate the extent to which a court may limit the scope of a cross-examination of a lay witness or party, as well as the cross of an expert witness, at trial.

Limitations on Cross

In his recent detailed order issued in the case of Detrick v. Burrus, No. 2011 CV 1333 (C.P. Lacka. Co. Feb. 23), Lackawanna County Court of Common Pleas Judge Terrence R. Nealon addressed a motion in limine filed by the plaintiff, Lori Detrick, in an automobile accident suit seeking to preclude evidence of a post-accident drug screen ordered by Detrick's treating doctor which contained a positive result for marijuana use.

Given that Detrick had denied any marijuana use under oath at her deposition, the defense planned to cross-examine her with respect to a urine drug test that was positive for marijuana, to attack her credibility as part of the overall search for the truth of the claims and defenses asserted by the parties at trial.

Citing Pennsylvania Rules of Evidence 401 and 403, pertaining to relevancy, Detrick contended that any evidence of the drug test was inadmissible because it was irrelevant and unduly prejudicial.

In addition to being relevant to attack the credibility of Detrick, who denied marijuana use under oath at her deposition, the defendant, Deidre Burrus, separately asserted that the evidence of the urine drug screen tests ordered by Detrick's post-accident doctor was also relevant to show that her own post-accident treating providers had serious concerns as to her use of prescription narcotic medications, such that the doctor felt it necessary to order a drug screen before prescribing medications to her.

In his opinion, Nealon noted that questions concerning the admissibility of evidence lie within the sound discretion of the trial court. In granting Detrick's motion in limine to preclude this evidence, the court relied upon the law that a witness may not be impeached or contradicted on a "collateral" matter.

Nealon noted that it is a well-settled principle of Pennsylvania law that "the purpose of trial is not to determine the ratings of witnesses for general veracity." The court reasoned that the Pennsylvania appellate courts have repeatedly held that "no witness can be contradicted on everything he testifies to in order to 'test his credibility.'" The court in Detrick also more specifically cited to a criminal court case holding that "general questioning concerning the use of drugs does not bear on the witnesses' 'character for truth.'"

The court also found that, even if such evidence was somehow relevant, this evidence was inadmissible under Rule 403, since its probative value was outweighed by the danger of unfair prejudice to Detrick.

The case, which was not appealed, therefore supports the notion that the permissible scope of a cross-examination of a party or lay witness is not unlimited. As noted below, the same rule prohibiting the cross-examination of a witness on collateral matters was recently applied in the context of expert witnesses.

Cross of an Expert Witness Also Has Limitations

By way of background, a few years back, a hot trend in Pennsylvania civil litigation matters involved the extent to which parties could discover information as to the extent of litigation-related activity by, and compensation for, opposing expert witnesses. Such discovery was gathered to be utilized at trial to expose experts as biased witnesses, or "hired guns," for the opposing side.

Over the years, since the handing down of appellate court decisions in Cooper v. Schoffstall, 905 A.2d 482 (Pa. 2006), and Feldman v. Ide, 915 A.2d 1208 (Pa. Super. 2007), allowing such discovery in limited circumstances, litigating attorneys gathered a treasure trove of such bias information pertaining to experts. Attorneys on both the defense and the plaintiffs side of the bar have amassed and shared such information on various experts, to the point that the information has become quite extensive with respect to certain experts.

Now that such voluminous discovery of litigation-related activity and compensation has been gathered on certain experts, the question has become to what extent all that information can be fairly utilized to cross-examine an expert at trial.

In its recent decision in Flenke v. Huntington, 2015 Pa. Super. 50, 467 MDA 2014 (March 17, 2015), the Superior Court ruled on the extent to which an expert may be cross-examined at trial with such large quantities of bias information discovered on that expert.

The Flenke case arose out of a motor vehicle accident. The question presented centered around the plaintiff's cross-examination of the defense's independent medical expert.
The Superior Court ruled that, while expert witnesses may generally be impeached for bias, including frequent work for the same side in litigation, there are limits to such cross-examination imposed by the law.

Under the well-established rule of law that holds that a witness cannot be cross-examined on collateral matters, the court in Flenke noted that even bias evidence can become too intrusive and so collateral, such that it should be limited, or even barred, at trial.

In Flenke, the plaintiff was permitted to cross-examine the defense expert as to the compensation earned by the expert in the case at hand, as well as other cases, within a reasonable limitation.

Yet, the Superior Court found that the plaintiff's effort to conduct a detailed review of the defense expert's 50 most recent reports involving other persons would have introduced collateral issues into the case. As such, this evidence was found to have been properly excluded by the trial court.

The court in Flenke also ruled that cross-examination pertaining to the expert's work for the defendant's insurance company was properly excluded, as it would have introduced the impermissible topic of insurance into the case.

Based upon the above cases, the extent to which the veracity of lay and expert witnesses can be tested at trial has some limitations. It appears that, under Pennsylvania law, while a witness can be exposed as a liar, liar, one cannot go so far as to symbolically light that witness' pants on fire.

Daniel E. Cummins is a partner and civil litigator with the Scranton law firm of Foley Comerford & Cummins. His civil litigation blog, Tort Talk, can be viewed at www.TortTalk.com.