Mass torts

A class action, class suit, or representative action is a type of lawsuit where one of the parties is a group of people who are represented collectively by a member of that group. The class action originated in the United States and is still predominantly a U.S. phenomenon, but several European countries with civil law have made changes in recent years to allow consumer organizations to bring claims on behalf of consumers.

In a typical class action, a plaintiff sues a defendant or a number of defendants on behalf of a group, or class, of absent parties. This differs from a traditional lawsuit, where one party sues another party for redress of a wrong, and all of the parties are present in court. Although standards differ between states and countries, class actions are most common where the allegations involve a large number of people who have been injured by the same defendant in the same way. Instead of each injured person's bringing his or her own lawsuit, the class action allows all the claims of all class members—whether they know they have been injured or not—to be resolved in a single proceeding.

The antecedent of the class action was what modern observers call "group litigation", which appears to have been quite common in medieval England from about 1200 onward. These lawsuits involved groups of people either suing or being sued in actions at common law. These groups were usually based on existing societal structures like villages, towns, parishes, and guilds. Unlike modern courts, the medieval English courts did not question the right of the actual plaintiffs to sue on behalf of a group or a few representatives to defend an entire group.

From 1400 to 1700, group litigation gradually switched from being the norm in England to the exception. The development of the concept of the corporation led to the wealthy supporters of the corporate form becoming suspicious of all unincorporated legal entities, which in turn led to the modern concept of the unincorporated or voluntary association. The tumultuous history of the Wars of the Roses and then the Star Chamber resulted in periods during which the common law courts were frequently paralyzed, and out of the confusion the Court of Chancery emerged with exclusive jurisdiction over group litigation. By 1850, Parliament had enacted several statutes on a case-by-case basis to deal with issues regularly faced by certain types of organizations, like joint-stock companies, and with the impetus for most types of group litigation removed, it went into a steep decline in English jurisprudence from which it never recovered. It was further weakened by the fact that equity pleading in general was falling into disfavor, which culminated in the Judicature Acts of 1874 and 1875. Group litigation was essentially dead in England after 1850.

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