Last month, the Pennsylvania Superior Court reinstated a case concerning the drug Risperdal, which had initially been dismissed mid-trial in 2016. Johnson & Johnson subsidiary Janssen Pharmaceutical's drug, Risperdal, is currently the subject of thousands of suits alleging that the drug directly caused gynecomastia in many young men.

The value of the reinstatement of T.M. v. Janssen for lawyers is that it clarifies laws about evidence, how courts determine evidence's reliability, and general lessons on procedural law. Although the evidence in contention in T.M. v. Janssen was specifically centered around pharmaceutical science, various court rules on an "expert opinion" can easily become applicable within many various areas of law.

The primary reason T.M. v. Janssen was initially dismissed reflects the common complications that arise in determining whether an issue is substantive or procedural. While this analysis can seem simple, it often is not, even for the most equipped lawyers and judges, and the outcome of this analysis is often determinative in a case. In T.M. v. Janssen, the trial court, in its dismissal of the case, followed Texas law, under which it found that plaintiffs' expert testimony regarding the researched qualities of Risperdal was not sufficient. The court held that, under Texas law relating to the sufficiency of expert scientific testimony regarding medical causation, plaintiffs had to produce "two epidemiological studies showing a statistically significant doubling" of the risk associated with taking Risperdal, and evidence that the plaintiff specifically affected by Risperdal, T.M., "was similarly situated to the patients" in the cited studies. See T.M. v. Janssen Pharmaceuticals, 2019 PA Super 217 (July 16, 2019). Plaintiffs argued that the question of sufficiency of evidence was a question of procedural law, and that Pennsylvania law, rather than Texas law, should therefore apply. On appeal, the Pennsylvania Superior Court agreed with the plaintiffs and reinstated the case.

What exactly is the difference between Pennsylvania and Texas law on this issue? The distinction lies in the two states' differing standards in admitting new scientific or technical information. Pennsylvania state courts still follow the Frye standard (see Pa.R.E. 702), whereas Texas state courts follow the newer Daubert standard. This variation in evidentiary standards is important for lawyers to know and remember—while Pennsylvania and a few other states still follow the Frye standard, Texas, like most states, and the federal courts, follow Daubert. As reference, Frye refers to the standard established in Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), whereas Daubert refers to the standard established in Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993).

Understanding the differences between these two common evidentiary standards is important for any attorney who may have to present expert evidence in court. In a certain sense, Frye and Daubert are not so different insofar as they both underscore the importance of evidence resulting from appropriate, generally accepted methods of research. These standards are designed to ensure that the quality of any scientific or other technical evidence introduced in a courtroom setting matches the standards of whatever field is in question in an otherwise regular context.

However, the Daubert standard is much more detailed and exacting than the Frye standard. Understanding the differences between Daubert and Frye is key for a lawyer who may have to practice between states and jurisdictions that use different standards—or simply for a lawyer who lives in a Frye state, like Pennsylvania, but also needs to do work in federal courts. In Frye states, the threshold for admitting new evidence in court is simply that the expert's opinion is generally in line with the respective field's methodology and standards. Pa.R.E 702 provides this in subsection (c), and in subsection (a) specifically allows experts to be anyone whose knowledge is beyond that of the "average layperson."

Daubert provides five prongs for analyzing the quality of expert testimony, as courts have a deeper responsibility under Daubert to decide whether the testimony is of sufficient quality to be admitted as evidence. Daubert courts also require that experts attend a hearing before they can testify. The five prongs used to evaluate experts and their testimony are nonexhaustive but provide a guideline for the in-depth consideration courts ought to give any novel evidence presented by an "expert." Trial judges, under Daubert, are instructed to consider these factors when establishing the validity of the methodology used to produce scientific or other technical evidence:

• Whether the techniques or theories in question can, and have been, tested;
• Whether the techniques or theories in question have been subject to peer review and publication;
• The known or potential error rate of these techniques or theories;
• The existence and maintenance of standards controlling the techniques or theories; and
• The level of widespread acceptance of this methodology within its relevant community.

The real implications of following either the Frye or Daubert standard in court are much less clear. At first glance, Frye might seem laxer—simply due to the lack of specifics it presents. And indeed, the Daubert standard was incorporated into Federal Rule 702 as an attempt to expand on Frye's shortcomings.

What do Daubert and Frye mean for judges, however? Then-Chief Justice William Rehnquist's partially concurrent, partially dissenting opinion on the Daubert ruling showed his skepticism of the implications of Federal Rule 702 now necessitating that judges had "either the obligation or the authority to become amateur scientists." He understood the importance of evaluating evidence's quality, but also questioned whether judges were all equipped with the knowledge to properly do so.

Some may find Rehnquist's opinion on the matter flippant. After all, one would hope that a judge deciding the validity of expert evidence understands basic science—no one wants their judge to admit bad evidence or take a quack at his word. Part of the departure from Frye is that Daubert asks for more than just general consensus. Again, judges under Daubert are not evaluating whether the evidence is true; they are evaluating for a general sense of reliability.

Is it that simple? The "gatekeeping" responsibility placed on judges is something that counsel needs to consider when they present scientific evidence in court. Your judge may know next to nothing about the area of expertise your evidence is coming from. Even if they have some knowledge, they, again, are most likely not experts in that field. Your expert testimony should thus be trustworthy and believable to the judge. And, most importantly, it should be reliable. Even if Daubert tries to evade the mere "consensus" sought by Frye, consensus is still a reliable heuristic for a judge to use. After all, a judge who is not an expert in a certain field is likely to trust the evidence if it results from methods presented which are well-accepted in that respective community. Since judges are not deciding on whether the evidence is factually correct, make sure that your expert's testimony and methodology cannot be reasonably questioned for validity by a judge.

Even if Pennsylvania still is a Frye state, attorneys who mainly practice within the state still ought to have a strong understanding of Daubert. Besides federal courts and many other states applying the Daubert standard (or adapted versions), recently, previously Frye states have shifted to the Daubert standard. Just earlier this year, Florida switched over to Daubert in its state courts. In this sense, Pennsylvania is an outlier, despite neighbors like New York and New Jersey also sticking to Frye.

There is no way to predict when, if ever, Pennsylvania might shift to a Daubert standard. In Florida, the state legislature attempted to emplace the Daubert standard a few years ago, but the state judicial system refused—only switching over this year during a major personal injury case decision involving expert testimony, see Delisle v. Crane, 258 So.3d 1219 (Fla. 2018). Other states that have recently switched over have also done so based on case law. A potential switch for Pennsylvania courts could be just around the corner.

The increasing role of science and technology in our lives helps explain the initial instatement of Daubert and especially its more recent spread throughout state courts. Considering the amount of technology used to just create, store and send documents on a daily basis, even cases that may appear purely legal, such as breaches of contract, might necessitate the testimony of technological experts depending on the complexity of the issues.

Making sure specialized knowledge can be trusted before it enters the courtroom is vital for the judicial system to ensure fair and just results. Even in states like Pennsylvania that follow the (on paper) the less stringent rules of Frye, this expectation of evidential integrity and clarity should be understood and followed by all legal practitioners.

Edward T. Kang is the managing member of Kang, Haggerty & Fetbroyt. He devotes the majority of his practice to business litigation and other litigation involving business entities. Conctact him at [email protected].