Civil procedure in the United States

Civil procedure in the United States consists of the rules of civil procedure that govern procedure in the federal courts, the 50 state court systems, and in the territorial courts. Civil procedures are distinct from criminal procedures in the US. Like much of American law, civil procedure is not reserved to the federal government in its Constitution. As a result, each state is free to operate its own system of civil procedure independent of her sister states and the federal court system.

Early federal and state civil procedure in the United States was rather ad hoc and was based on traditional common law procedure but with much local variety. There were varying rules that governed different types of civil cases such as "actions" at law or "suits" in equity or in admiralty; these differences grew from the history of "law" and "equity" as separate court systems in English law. Even worse, discovery was generally unavailable in actions at law. In order to obtain discovery, a party to a legal action had to bring a collateral proceeding, a bill in equity in aid of discovery, just to obtain essential documents or testimony from the opposing party.

Procedure in the early federal courts was rather incoherent. The Process Act of 1792 authorized the federal courts to write their own procedural rules for everything but actions at law. In the context of actions at law, the Process Act of 1789 was so poorly written that it forced a federal court sitting in a state to apply the common law rules of pleading and procedure that were in effect in the state at the time it joined the Union, regardless of whether the state had modified or revised its civil procedure system since. In other words, even though a state's common law pleading system was always constantly evolving through case law, the federal courts in that state were literally frozen in time. The Process Act did not speak to the problem of what law to apply in new states that joined the Union after the original Thirteen Colonies. In 1828, Congress enacted a law which stated that federal courts in new states would follow the civil procedure in effect at the time those states joined the Union.

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