download (1).jpgBy Tim Haley

In Cason-Merenda, et al. v. Detroit Medical Center, Case No. 06-CV-15601, 2013 U.S. Dist. LEXIS 5707 (E.D. Mich. Apr. 22, 2013), Judge Rosen of the U.S. District Court for the Eastern District of Michigan held that the expert report provided by the plaintiff Registered Nurses (“RNs”) satisfied the Daubert admissibility requirements. 

In so ruling in this workplace antirust class action, Judge Rosen applied a fairly lenient interpretation of the Supreme Court’s decision in Daubert v. Merrell Down Pharmaceuticals, Inc., 509 U.S. 579 (1993), describing its gatekeeping role as limited and noting that the rejection of expert testimony is the exception rather than the rule. Cason-Merenda, 2013 U.S. Dist. LEXIS 5707, at *19-20. But what will be interesting is how Judge Rosen will deal with this expert testimony in deciding the pending motion for class certification.  In his decision Judge Rosen repeatedly refused to resolve issues involving a “battle of the experts,” holding that such determinations were for the trier-of-fact. Id., at *28-29, 38, 40-41, 46. Given recent Supreme Court precedent, it remains to be seen if the Court can take that position in deciding the motion for class certification.

The ruling is instructive for employers dealing with expert testimony in workplace class actions.


In December 2006, plaintiffs, two registered nurses (“RNs”), filed a purported class action complaint alleging that a group of hospitals in the Detroit Metropolitan Area (“DMA”) violated §1 of the Sherman Act. In count I plaintiffs alleged that the hospitals conspired to suppress nurse wages and that this conduct violated §1 per se. In count II plaintiffs alleged that the hospitals agreed to exchange compensation information and that the effect of the exchange was to suppress nurse wages in the DMA in violation of §1 under the rule of reason. In March 2012, the Court granted the defendants’ motion for summary judgment on count I but denied it as to count II. (We previously blogged on this decision here.)  Still pending is the plaintiffs’ motion for class certification.  In reports provided by plaintiffs’ expert, Dr. Orley Aschenfelter opined that he could show with common proof that: (1) all or nearly all members of the class suffered harm (antitrust impact); and (2) the measure of each class member’s lost earnings. Id., at *11. In this motion defendants sought to exclude Dr. Aschenfelter’s testimony under Daubert.

The Decision

Dr. Aschenfelter proposed to show the wages the class members would have earned had there been no conspiracy (the “but-for” wages) by using a “benchmark” or “yardstick” methodology comparing the wages paid to RNs to what the hospitals paid for registered nurses supplied by temporary agencies. The defendants’ principal challenge to this method was that Dr. Aschenfelter failed to make the substantial adjustments necessary to ensure that the agency fee benchmark was “reasonably comparable” to the “but-for” wages that the hospitals would have paid to their RNs. Id., at *25. The Court noted that Dr. Aschenfelter did make adjustments to account for the differences and that challenges to the completeness or accuracy of those adjustments were matters affecting the weight to be given to the testimony and not its admissibility. Id., at *25-33.

Defendants also challenged Dr. Aschenfelter’s benchmark analysis on the grounds that it generated a single “but for” wage figure encompassing all nurses that worked at a given hospital in a given year and failed to distinguish between nurses with differing levels of experience, skill and training. In fact, Dr. Aschenfelter conceded that his method may result in understating the losses of experienced nurses as compared to the losses suffered by their less experienced counterparts. Id., at *33-37. However, the Court held that this was not a basis for excluding Dr. Aschenfelter’s testimony. So long as Dr. Aschenfelter was able to convince a jury that his benchmark methodology provides a truly conservative estimate of the RN losses, the Court reasoned that then his testimony was admissible on the issue of common antitrust impact. Moreover, the Court noted that the Sixth Circuit had upheld an aggregate measure of damages in an antitrust case that rested upon a uniform impact theory similar to that advanced by Dr. Aschenfelter. Id., at 34-37.

Implications For Employers

While Judge Rosen was able for now to avoid resolving the expert battles he noted in his decision, he may not be able to do so when he decides the motion for class certification. Recent cases have held that a court must resolve issues involving a battle of the experts if they are relevant to the question of whether class certification is appropriate. See, e.g.,Ellis v. Costco Wholesale Corporation, 657 F.3d 970, 982-84 (9th Cir. 2011). Further, Dr. Aschenfelter’s admission that his methodology may understate the losses of experienced nurses as compared to the losses suffered by their less experienced counterparts raises questions as to whether plaintiffs can adequately represent more experienced nurses. In addition, some courts have read the Supreme Court’s recent decision in Comcast Corp. v. Behrend, 2013 U.S. LEXIS 2544 (U.S. Mar. 27, 2013), to hold that to certify a class, plaintiffs must show a common method for proving the amount of damages suffered by each class member. The question is whether Dr. Aschenfelter’s method of estimating damages on a class-wide basis satisfies that standard.