What Is a "Mass Tort"?

When unsafe products and other dangers cause widespread harm, mass tort lawsuits can provide a legal remedy.

By , Attorney · South Texas College of Law Houston
Updated by David Goguen, J.D. · University of San Francisco School of Law

Almost all "tort" or personal injury cases revolve around a single wrongful act (like a car accident) that injures one or two people, who end up filing claims for the harm they've suffered. But when many people are injured by the same wrongful conduct, or by the same harmful product or material, "mass tort" lawsuits might be possible.

What Constitutes a "Mass Tort"?

In the eyes of the law, a "tort" is a civil wrong, as opposed to a criminal wrong. In civil lawsuits based on tort law (also known as personal injury law) the injured person must prove that the bad act, whether intentional or negligent, harmed them in some way.

Tort or personal injury lawsuits are intended to compensate the injured person instead of punishing the wrongdoer—although in injury lawsuits the wrongdoer is "punished" by having to pay court-ordered compensation (damages) to the injured person.

There's no universal definition, but typically "mass tort" civil lawsuits are those in which hundreds or even thousands of plaintiffs (injured people) have brought similar cases against one or a few defendants (usually manufacturers or other corporations). Examples of mass tort litigation include:

The Benefits of Mass Tort Cases

A primary benefit of mass tort litigation is what's know as "economy of scale." Lawsuits are costly, and individuals can't always afford to prosecute their claims against big corporations alone. In civil litigation, plaintiffs have the burden of proving that:

  • the defendant's wrongful conduct caused their injuries (causation), and
  • that their injuries are real (damages).

Because plaintiffs have the burden of proof, the costs of proving these cases can be significant. Mass tort plaintiffs in class actions and multi-district litigation (explained below) benefit from shared research (called "discovery") that their lawyers use to prove that the defendants' wrongful conduct caused their injuries.

Highly qualified experts testify in these cases to prove the defendants' liability and the extent of the plaintiffs' damages. The expert witness fees alone could bankrupt anyone who's not independently wealthy. Mass torts provide economy of scale because the costs associated with proving causation are borne by all plaintiffs, as opposed to each plaintiff having to individually prove their own case.

Mass Torts and Multi-District Litigation

Mass tort plaintiffs typically live in geographically diverse locations. Consider unreasonably dangerous medications. The manufacturer markets the drug nationwide, and it's possible that consumers in all 50 states will suffer harm as a result. If each plaintiff were to file an individual lawsuit, the court system would be overwhelmed with hundreds or thousands of cases with the same or very similar:

  • underlying facts
  • issues of liability, and
  • medical/scientific evidence.

This is a big reason why mass tort lawsuits are often good candidates for "multi-district litigation" or MDL. Learn more about how multi-district litigation works in mass tort cases.

Why Class Actions Aren't Usually a Good Fit for "Mass Tort" Cases

Class actions are usually reserved for cases where each affected person's damages are primarily economic, like situations where a company negligently (or fraudulently) added excess charges alongside the provision of a product or service. In these cases, it's fairly easy to assign a value for each customer's losses.

But sometimes a common wrongful act causes damages that vary greatly from plaintiff to plaintiff. For example, a defective medical device can fail in a similar way for each patient, but the nature and extent of injury suffered by each patient can vary (and subjective impact like "pain and suffering" can differ significantly from claimant to claimant). Cases like these aren't good candidates for class actions, and are more likely to be prosecuted in multidistrict litigation (MDL), as explained in the previous section.

Note that consumer protection-focused class action lawsuits are possible when a product or drug turns out to be dangerous. In cases like these, class members bought the product or drug in question, but usually weren't harmed by using it. These kinds of class actions typically allege deceptive marketing or similar wrongdoing on the part of the manufacturer, but include no claims for illness or injury.

Getting Help With a Potential Mass Tort Case

When you're thinking about taking legal action against a company that you think has caused you significant injury or illness, you're probably not all that concerned with whether or not you've got a potential mass tort case on your hands. You're likely (and justifiably) focused on protecting your legal rights and setting your case up for success.

It's a personal injury lawyer's job to figure out the best course of action for your case, and to work toward the best result. Learn more about finding the right personal injury lawyer for you and your case.

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