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What is a Bellwether Trial?

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A bellwether trial is a test case that helps determine how other similarly situated cases will fare in the future. They are an important measurement for cases in a mass tort, where individual cases making similar allegations against a common defendant (or defendants) are consolidated in a multidistrict litigation (MDL) at the federal level or a state court equivalent.

At Wisner Baum, our attorneys are currently preparing for bellwether trials in the following cases:

Zantac cancer litigation (California and Delaware state courts)

Toxic baby food litigation (California state court)

Gardasil vaccine MDL (North Carolina federal court)

In this blog, the mass tort lawyers at Wisner Baum discuss the purpose of bellwether trials, why bellwethers are used in mass tort cases, how bellwether cases are selected, and what the results of bellwether trials can have on other similarly situated cases.

Bellwether Trials Explained

What is a Mass Tort?

How Does the Bellwether Selection Process Work?

Do Bellwether Trials Affect Other Cases in a Mass Tort?

What Happens After a Bellwether Trial?

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What is a Mass Tort?

Before we delve into the intricacies of bellwether trials, it is important to understand why they are necessary. When numerous personal injury cases make similar allegations against the same defendant (or multiple defendants), the courts face a challenge in thoroughly investigating each case individually. Instead of having each case tried individually, the court may establish a mass tort, grouping individual lawsuits that make similar allegations into a consolidated multidistrict litigation (MDL). It's worth noting that an MDL, while similar to a class action involving many individuals, differs from a class action in that each case in the litigation is not tied to the outcome of the entire class.

In an MDL, the overseeing judge combines the discovery and pretrial proceedings for all consolidated cases. For example, Wisner Baum is currently co-leading the Gardasil vaccine MDL against the vaccine’s manufacturer, Merck. Over 180 plaintiffs from across the country have filed lawsuits against the defendant. These cases have been consolidated in North Carolina federal court.

Similar consolidations are also possible at the state court level. Our firm is co-leading the Zantac cancer litigation, where over 4,000 lawsuits have been filed and consolidated in California state court, and nearly 75,000 lawsuits have been filed and consolidated in Delaware state court.

During the MDL process, the attorneys representing the plaintiffs (the people who are suing defendants) typically submit a joint complaint, to which the defendants respond in federal court. Both sides of the legal dispute engage in fact discovery to gather information relevant to all cases, commonly called "general liability" discovery. The judge then establishes a bellwether system to choose and hear representative cases in the MDL. Despite this collective approach, each individual plaintiff's case remains distinct and may return to their original district court for trial after the conclusion of the MDL proceedings.

How Does the Bellwether Selection Process Work?

Most often in mass torts, attorneys for both plaintiffs and defendants select an equal number of cases as bellwether trial candidates. This initial “pool” of cases can range from around 10 cases (five each for the plaintiffs and the defendant) to many more if the litigation has thousands of cases. Bellwether candidates can also be randomly selected by a computer using parameters set forth by the overseeing judge.

Selecting cases from the pool to be tried typically involves each side choosing an equal number of cases they believe are most favorable. Sometimes, the MDL judge may also play a role in selecting bellwether cases. In the 3M earplugs litigation, for example, the first bellwether trial involved three plaintiffs. One was selected by the plaintiffs lawyers, one was selected by the defense, and one was selected by the MDL judge.

To summarize, there are generally four approaches for selecting bellwether trials that involve the judge, the lawyers, random selection, or a combination. Most courts opt for a hybrid approach, allowing attorneys from both sides to have input, but ultimately, the court decides which cases proceed to trial and in what order.

Do Bellwether Trials Affect Other Cases in a Mass Tort?

Bellwether trials can impact other cases in a mass tort litigation, but the outcome of one trial does not directly impact other cases. Let’s say, for example, the plaintiffs are successful in the first bellwether trials in a mass tort. After losing multiple times in court, the defendants may be more inclined to settle the remaining cases to avoid potentially more significant verdicts in future trials.

The rulings and legal arguments made in bellwether trials can also set precedent for how other cases in the mass tort will be handled. For example, a judge's decision on the admissibility of certain evidence in a bellwether trial may impact how that evidence is handled in other cases.

What Happens After a Bellwether Trial?

After the first bellwether trial, plaintiffs in a mass tort may sense that the litigation is coming to a close, especially if the verdict is in favor of the plaintiff. However, this is not always the case; the defense may try at least a few more cases before ultimately deciding if a settlement is the best course of action.

If both sides are unable to settle the litigation after multiple bellwether trials, the judge may send the cases back to the courts from which they originated. When this happens, the MDL usually dissolves, and the cases are tried individually.

The vast majority of mass torts culminate in a settlement, but sometimes plaintiffs can wait years until the litigation is resolved.

Get a Free Case Evaluation

If you or a family member were harmed by a defective product, you may be able to pursue justice and compensation in a lawsuit. At Wisner Baum, we have developed a reputation as a law firm that can be counted upon to go above and beyond what is needed to obtain justice and compensation. Our team of lawyers has what it takes to successfully litigate personal injury and wrongful death cases against any corporate defendant. But don’t just take our word for it; read our client reviews and see our case results yourself.

To speak with a Los Angeles injury attorney about your case, contact us today or call 855-948-5098. We offer free and confidential case evaluations.


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