A mass tort is a civil lawsuit that involves hundreds or thousands of plaintiffs and one or a few defendants in which the plaintiffs have the same or similar claims against the defendant or defendants. Mass tort lawsuits are often filed as class action lawsuits (a procedural mechanism for joining the plaintiffs in one lawsuit), and are typically based on alleged wrongful acts (torts) such as exposure of the plaintiffs to harmful substances (asbestos or benzene), or defective products (pharmaceuticals or medical devices), or invasions of privacy (data breaches).

In Wisconsin, as in other states, a mass tort is a type of civil action involving numerous plaintiffs against one or a few defendants where the claims arise from common issues such as exposure to harmful substances, defective products, or invasions of privacy. These cases often involve complex legal and factual questions, and they are typically coordinated for pretrial proceedings to streamline the legal process. While mass torts can be filed as class actions, they may also proceed as individual lawsuits that are grouped together for efficiency. Wisconsin state statutes and federal laws, including the rules governing class actions (Federal Rule of Civil Procedure 23), apply to these cases. The Wisconsin court system is equipped to handle mass torts, and there are specific procedures in place to manage these large-scale litigations, including the potential for multidistrict litigation (MDL) when cases span multiple jurisdictions. An attorney specializing in mass torts or class actions would be able to provide more specific guidance on the intricacies of pursuing such a lawsuit in Wisconsin.