It is an old legal adage that hard cases make bad law. One could also say that big cases make bad law, especially if by “big” we include Multi-District Litigation (MDL) cases. When a federal judge is suddenly in charge of thousands of cases, that judge will too often start thinking more like a manager than a scholar. The emphasis is on disposition of the inventory. That means settlement. Consequently, we get decisions, or often non-decisions, that are designed to foster settlement, not resolve complex legal issues in an intellectually coherent way.

But then something strange happens near the end of the life-cycle of MDLs. After the bulk of the cases are settled, there remains a “tail” of cases or about-to-be-filed cases. Those cases are holdouts. They are in the hands of plaintiff lawyers who are opportunistic and/or recalcitrant. At this point, the MDL judge gets a wee bit irked, seeing these holdouts as standing in the way of ending the MDL and giving the judge something to brag about at the next judicial conference. So what happens? All of those defense dispositive motions that earlier met with a shrug, including statute of limitations motions, suddenly start gaining attention. They even start winning. One doesn’t have to be entirely cynical to wonder why they weren’t winning much earlier in the litigation.

The vaginal mesh MDL (technically multiple MDLs – each manufacturer getting its own MDL number, but still sharing the Charleston, West Virginia courtroom with other mesh companies) has been a big one even by MDL standards. It has also produced some rulings that have left the defense bar scratching heads and contemplating other lines of work. For example, vaginal mesh MDL rulings have kept out the fact of FDA 510(k) clearance, which, contrary to the court’s opinions, really is relevant to the medical device’s safety, but have let in the raw materials Material Safety Data Sheet (MSDS) which, contrary to the court’s opinions, really is not. (There are some courts that have correctly admitted the fact of 510(k) clearance. See here and here, for example.)

But the Daubert rulings in the mesh MDL have not been entirely bad. Naturally, we defense hacks think the court let too many plaintiff expert windbags opine on things sans support, reliable methodology, or relevance, but any perusal of the court’s Daubert opinions will show that the court did the one thing that Daubert requires and that too many judges resist: it did the work. The court read the expert reports carefully, read whatever was supposed to pass for support of the opinions, and considered the competing arguments. The result was a series of opinions that let some things in and kept some things out. Again, we’d have to turn in our DRI card if we did not carp about some of these Daubert rulings. Nevertheless, by showing its work and drawing distinctions, the mesh MDL court created the sort of record that will force any appellant to sweat.

The vaginal mesh cases are now being remanded. In many of those cases, Daubert issues remain to be adjudicated. Not surprisingly, some remand courts are displeased. But they have a pattern to follow, at least mostly. The remand courts continue to pick and choose which expert opinions to wave along and which ones to block. In Arevalo v. Coloplast Corp., 2020 U.S. Dist. LEXIS 124417 (N.D. Fla. July 7, 2020), the court ruled on Daubert challenges in a case involving pelvic organ prolapse and stress urinary incontinence mesh implants. The opinion is the veritable mixed bag, granting parts and denying parts of various Daubert challenges for a long list of experts, both plaintiff and defense sides. Several of the experts are repeat players; many of us have dealt with them many times.

The Arevalo court excluded many plaintiff expert opinions, and we will summarize those exclusions. The court also let plenty of those opinions in, and also excluded some defense expert opinions. You will want to read the entire opinion before citing the case, of course. But at this point we are not in the business of broadcasting any help-aids for plaintiff lawyers. They’ll have to read the opinions for themselves – a surprisingly high barrier to entry for our learned opponents.

    Alan Garely

– Plaintiff general causation expert
His general opinion was unreliable because he did not adequately explain how the cited literature and his observations supported his opinions that the injuries associated with the prolapse product are directly attributable to the device’s reaction in vivo and defective design.

    Jimmy Mays

– Plaintiff polymer science expert
His assumption that strong oxidizing agents in the body “continually” attack the polypropylene as long as the implant remains in the body is not adequately supported. His opinion that oxidation agents deplete the antioxidative additives during the lifetime of the implant is unreliable because he did not test the defendant’s products nor rely on literature that involved such testing.
His reliance on an article he co-authored is excluded because that article’s testing was unreliable. (That’s a bit of a burn.)
His opinions on medical complications is excluded because he is not a medical doctor.
He is permitted to rely on the MSDS (the biggest takeaway from the vaginal mesh litigation might end up being the phony significance of the MSDS) but cannot use the MSDS to render toxicology opinions, as he is not a toxicologist.

    Peggy Pence

– Plaintiff regulatory and industrial standards expert
It is not clear how she was permitted to testify at all, given the MDL court’s no-FDA evidence ruling. Nevertheless, the Arevalo court permits her to say quite a bit, though there are some limits. For instance, Pence cannot testify that the defendant was “required” to do something by FDA guidance documents. And while she can explain industry standards and the need for testing generally, she cannot draw the ultimate conclusion that the defendant’s testing was inadequate.
Pence will be permitted to discuss the adequacy of the IFUs (mind you, these are IFUs cleated by the FDA), but cannot opine about informed consent.

    Bruce Rosenzweig

– Plaintiff general and specific causation
The Arevalo held that “the causes of polypropylene degradation, polymer compounding, the products of polypropylene degradation, or the toxicity of of any such degradation product are subjects that are not within his area of expertise. Despite other courts finding that Dr. Rosenzweig qualifies to opine on these topics, the Arevalo court “cannot because, by his own admission, he is not an expert in polymer science, chemistry, molecular biology, biochemistry, or toxicology.”
Further, the court was “not persuaded that Dr. Rosenzweig employed a reliable methodology in forming his general causation opinion (i.e., that polypropylene mesh degradation causes pelvic pain, vaginal pain, dyspareunia, frequent UTIs, urinary and fecal incontinence) because although articles cited by Dr. Rosenzweig conclude that polypropylene mesh degrades in vivo, the Court did not see that any explained the mechanism by which degraded mesh causes the injuries alleged by Plaintiff, nor any that offered the ultimate conclusion that degradation of the mesh can cause these injuries in humans.” That is potentially a powerful ruling because so many plaintiff urogynecological experts in the mesh litigation make the casual leap from mesh degradation (also phony, by the way) to clinical consequences.
His testimony that the product is defective because it lacks a protective sheath is excluded because it is based on speculation or mere anecdotal evidence.
Dr. Rosenzweig can discuss how the mesh has small pores, but he does not provide a basis for his opinion that the mesh is heavyweight. Moreover, his opinion that the product requires a “blind” needle passage was merely subjective and conclusory. There was no supporting data.
As is typical in mesh cases, Dr. Rosenzweig opined about the availability of safer alternative designs. Several of those opinions were excluded in Arevalo. He did not supply an adequate basis to explain why products with less polypropylene, different shapes, larger pores, etc. would be safer. His references to non-sling alternatives such as the Burch procedure and autologous (tissue) slings must be excluded because those are not alternative products,
The decision regarding Dr. Rosenzweig’s opinions on informed consent looks like classic baby-splitting. He can talk about it generally, but not specifically, since he cannot read the mind of the plaintiff or her doctor.
As usual, Dr. Rosenzweig purported to ground his ultimate specific causation opinions on a “differential diagnosis.” The Arevalo court was not snookered by this incantation. Instead, the court looked carefully at Dr. Rosenzweig’s “differential diagnosis” and concluded that so much of it was mere say-so. He did not “explain how he systematically and scientifically ruled out the other potential causes for Plaintiff’s condition, such as her rectocele, cystocele, or uterine prolapse. Even if multiple factors work together to cause the injury, the expert is still required to provide some analysis of why he concluded that, more likely than not, the product substantially contributed to the condition.”
Dr. Rosenzweig’s opinions about the insufficiency of the defendant’s testing fell short of reliability because they were based solely on his his own view of what a reasonable manufacturer should have done, rather than any objective standards.

As mentioned, there is a lot more to the Arevalo opinion. If you cite its good parts you must anticipate the possibility that you will be saddled with its bad parts. Just like the treating doctors, or like any expert who actually plays the role conscientiously, you must perform a rigorous risk-benefit analysis.