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Introduction to Mass Torts Overview - Module 1 of 5

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Module 1:  Introduction to Mass Torts


Traditionally, when we think of torts, we think of individualized wrongs one person commits against another. We might think of negligence — for example, someone who is driving too fast or carelessly causing an accident which injures people and property. We also might think of premises liability, when a store does not show reasonable care in maintaining the condition of the store and allows a wet spot in an aisle to persist without warning customers, causing one to slip and fall.

Another, more recently developed kind of tort is product liability, where a manufacturer or seller of a product is liable if it is defective.  For example, the manufacturer of a ladder might be liable if the ladder collapses when used because the ladder’s rungs were not properly installed or designed. These kinds of torts are individual wrongs with individual remedies.  One plaintiff, or maybe a few plaintiffs, bring an action against the tortfeasor who caused the injury. 

            In recent decades, though, a new type of tort claim has evolved, called the “mass tort.”  Many would date mass tort litigation to the early 1960s, with the MER/29 litigation, which concerned the side effects of a drug that was intended to lower cholesterol but that had severe undisclosed side effects.[1]  These “mass torts” arise when hundreds or even thousands of claimants allege injuries arising from exposure to the same product or catastrophic event. 

            Perhaps the best-known mass tort litigation with the greatest number of claimants has been the various types of asbestos litigation, concerning both personal injury and property damage. It concerned the health effects of exposure to the formerly widely used mineral, asbestos, and the costs for replacing asbestos materials used in buildings like public schools.[2]  Most mass torts, though, involve prescription drugs or medical devices.[3] Historical mass torts include claims arising from herbicides like Roundup[4] and claims that automobiles contain defective parts, as when certain models of General Motors cars were alleged to have had defective ignition switches.[5]

             One key characteristic of a mass tort is that the alleged wrong is spread out over a very large number of victims.  Courts must handle all of the victims’ claims in a collective fashion to be efficient and fair to both plaintiffs and defendants. In the federal court system, there are two ways that a mass tort action can be coordinated.  First, it can be done as a class action under Federal Rule of Civil Procedure 23,[6] or second, the claims can be aggregated under multidistrict litigation procedures which were established by Congressional statute in 1968, a statute now codified as 28 U.S.C. § 1407. We’ll refer to multidistrict litigation as “MDL” throughout the course.    

Defining Mass Torts

            Defined broadly, mass torts include a wide variety of claims, including allegations based on defective automobile design, safety equipment used in sports, defective pharmaceuticals or medical devices and even airplane crashes, train wrecks, oil spills and the aftereffects of the 9/11 terrorist attacks.  Defined in this broad way, the term “mass torts” encompasses most claims being litigated in federal courts as MDL claims and all the class action tort claims being litigated.[7]  However, it is useful to divide this broad range into three smaller categories:

-       mass accident cases,

-       toxic tort cases, and

-       “True” mass torts.

            Mass accident cases are those that arise from a catastrophic event that injures many people or causes damage to many different owners’ properties.  The catastrophic event could be an airplane crash (such as the one over the southern Indian Ocean in 2014), a giant offshore oil spill (such as the Deepwater Horizon spill in 2010), a hotel fire (such as the MGM Grand Hotel fire in 1980), or any other similar event.  The defining characteristic of this case is that, although the plaintiffs might be found in a large number of different parts of the country, the actual harm the plaintiffs suffered arose from a distinct event in a specific place at a specific time. Thus, the claims all are centered in one place and focus on one point in time.  Though there may be a very large number of such claims, and the plaintiffs may be spread all across the country and even the world (such as the families of people who died in an airplane crash), the event that gives rise to these claims differs from other tortious activity, where the defendant’s alleged negligence causes a particular bad event.

            Toxic tort cases push the boundaries of traditional torts.  The typical toxic tort involves something like the spill of a toxic substance that might cause several people to develop illnesses, sometimes over long periods of time, perhaps even decades.[8]  In toxic tort cases, the actions are geographically confined, though the harmful effects may take a long time to be discovered.  An example might be a chemical plant that allows a toxic substance to leak into the local water table.  People may get sick a long time later and may continue to get sick, but the toxic event is geographically localized.  The toxic tort has a geographic center, and it is likely that all claims arising from that toxic tort will be brought in the same federal district or state court. 

            Finally, there is the true mass tort, which means a tort action that requires the new and innovative procedures for collective treatment of claims that can be found in class actions and multidistrict litigation.  There may be thousands or even tens of thousands of individual claims, which are often called the “constituent claims” of the mass tort, but they are treated collectively in the courts, in a process often referred to as “aggregation.” 

            These “true” mass torts not only give rise to a vast number of claims, but the tortious events on which the claims are based may be widely dispersed in both time and space. Though they arise from one “wrong,” such as a defective medical device or drug, they cause widespread harm that may occur over a long stretch of time throughout the entire country or beyond.

            Some of the most significant and well-known mass tort actions are those that arose from claims over the use of asbestos.  Asbestos is a hypothetically useful mineral because it can be pulled into soft, flexible, fireproof, and heat resistant fibers and is resistant to electricity and chemical corrosion. Pure asbestos is an effective insulator, and it can be mixed into cloth, paper, cement, plastic and other materials to make these substances stronger.  Unfortunately, the fibers themselves can get into the lungs of those who work with the substance and these fibers are very toxic, leading to diseases like asbestosis and mesothelioma.  A few companies mined and manufactured asbestos-containing products for decades, and hundreds of thousands of workers were exposed to the fibers.  There also was evidence that these companies knew of the dangers of the product but hid them from both the public and the workers. The asbestos claims arose from one common type of product, and one common alleged wrong (the decision to make the product and hide its dangers), but the injuries took place all over the world over the course of several decades. 

            Other mass torts of this sort that have arisen in the last few decades include claims from the sale of the Dalkon Shield, an intrauterine birth control device; claims that the dangerous side effects of various pharmaceuticals were not disclosed; claims by Vietnam War veterans arising from the use of Agent Orange, a defoliant; claims against Roundup, the weed-killer; claims about defectively designed hip implants; and claims by former NFL players that the NFL knew about, but hid, the dangers of concussions to players. There can be many thousands of plaintiffs in these claims from every state.  As a result of the size and the scope of these claims, courts have begun to use the special procedures that we will be examining in this course.

Product Liability Cases


            One important characteristic of most mass torts is that they are usually versions of product liability claims.  Product liability actions dominate currently active multidistrict litigation.[9]  Specifically, most mass torts arise under claims that a product was defectively designed or that the defendant manufacturers did not provide effective warnings. Many of the mass tort claims concern pharmaceuticals, and often concern failures to warn of their dangers or risks. The plaintiffs claim injuries, illnesses or adverse health conditions caused by the way the medicine was marketed, in that the manufacturers failed to provide adequate warnings regarding dangerous side effects or failed to provide instructions regarding the safe and appropriate use of the drug. The defenses to these claims often rely on the fact that the Food and Drug Administration mandated certain information be provided with the pharmaceutical and that the company complied with the mandate. Though compliance with FDA guidelines and rulings does not guarantee successful defense, it can be used as evidence to rebut claims of negligence.


            Another large category of mass tort involves medical devices, such as hip implants. These claims often allege that the design of the device was defective because a better and safer alternative was reasonably available to the manufacturer. The same kinds of design defect claims are often at the core of the mass tort actions against the makers of various insecticides and herbicides, like Roundup or Agent Orange.


            The fundamental theories of liability and the legal defenses to these theories are no different than those for traditional, individual product liability claims.  However, in mass tort actions, some key issues that will impact the thousands of claims are common. There are core common issues that give impetus to the effort to treat mass torts in a collective rather than individual fashion.


Common Issues of Fact and Law


            One hallmark of multidistrict litigation is that common issues of fact or law permeate all of the constituent claims.  In fact, the courts must find that there are common issues of fact or law, and these must be significant and controlling issues, before the courts can aggregate the claims to form a class action or multidistrict litigation.  Such a finding is a prerequisite to forming a class under Federal Rule of Civil Procedure 23 or creating a multidistrict litigation under 28 U.S.C. § 1407. 


            There usually are at least three common factual issues.  First, each of the claimants is exposed to the same product in a similar way.  For instance, in the Dalkon Shield Litigation, each claimant used the contraceptive device in question.[10]  Similarly, in the NFL Concussion Litigation, each claimant was a former NFL player who suffered head injuries.[11] The second common issue is that all claimants are challenging the same allegedly negligent decision of the defendant.  That could be the decision to design a product in an unsafe way or to market the product using deficient warnings and instructions.  Third, the causal mechanisms for all the claimants’ injuries are similar.  That is, the product is alleged to have harmed each plaintiff substantially the same way. To cite a rather obvious example, if a patient slipped and fell on a puddle caused by the spill of an allegedly defective drug, that patient’s lawsuit would not belong in the same multidistrict litigation or class action as those alleging to have been injured by ingesting the defective drug.


There are also often common defenses to mass tort actions.  One frequent defense in pharmaceutical cases, for example, is FDA rules preempting state law on a subject. Another common defense is assumption of risk, that is, the consumers knew of the risks inherent in a product and chose to take it anyway.


            There are, however, also issues that arise in mass tort cases that are individual to each constituent claim.  Each plaintiff has suffered individual damages which can differ from person to person. There may be differences in how much and how long each person was exposed to the product.  Moreover, as tort claims are generally governed by state law,[12] there may be differences in how the legal doctrines of the various states evaluate the same set of facts. One state may apply a different test than another to decide whether a warning is effective, for instance. Therefore, the collective treatment of the constituent cases must also accommodate the individual differences among them.


Collective treatment

            It has seemed obvious to many courts that claims arising from these mass torts should be handled in an aggregate or collective way.  If there were no way to treat them collectively, litigating each constituent claim separately probably would bankrupt the defendants with legal costs and other resources required to defend the claims, leaving no money to pay claims. It would also overwhelm the courts.

            Currently, there are two ways to aggregate such claims.  The oldest and best known is the class action.  But, the most common way of handling mass torts in today’s the federal courts is through Multidistrict Litigation, which was created by federal law in 1968.[13]  Currently, approximately 39% of cases in the federal district courts are part of MDL actions.[14] In the following two modules, we will examine these two ways to aggregate mass torts actions. In module 2, we’ll discuss class action lawsuits and then turn to multidistrict litigation in module 3.

[3] See Paul Rheingold, Litigating Mass Tort Cases C.15.1 (AAJ Press 2006).

[4] Ondes v.Monsanto Co., No. 4:11CV197 JAR, 2011 U.S. Dist. LEXIS 142604 (E.D. Mo. Dec. 12, 2011).

[5] Greenroadv. GM (In re GM LLC Ignition Switch Litig.), No. 14-MD-2543 (JMF), 2017 U.S. Dist. LEXIS 213074 (S.D.N.Y. Dec. 28, 2017).

[8] e.g., the book and movie “A Civil Action” concerned just such a toxic tort case arising from contamination of the water around Woburn, Massachusetts. 

[9] U.S. Judicial Panel on Multidistrict Litig., Calendar Year Statistics: January through December 2016 11 (2017), http://www.jpml.uscourts.gov/sites/jpml/files/JPML_Calendar_Year_Statistics-2016.pdf [https://perma.cc/RA2G-LLLD].

[10] Waitekv. Dalkon Shield Claimants Tr., 908 F. Supp. 672 (N.D. Iowa 1995).

[11] Turner v. NFL (In re NFL Player’s Concussion Injury Litig.), 307 F.R.D. 351 (E.D. Pa. 2015).