Discovery (law)

Discovery is a vital phase of pretrial procedure in common law jurisdictions. It allows each party in a lawsuit to obtain evidence from other parties. This process is governed by the law of civil procedure. It ensures that both sides have access to the facts before a trial begins. Discovery uses several specific methods to gather this information. These include interrogatories, which are written questions. There are also requests for the production of documents. Parties may use requests for admissions or depositions. If a party is not involved in the suit, a subpoena can be used to obtain evidence from them.

When the process does not go smoothly, the court must intervene. If a party refuses to provide information, the requester may file a motion to compel discovery. This asks a judge to force the other side to comply. Conversely, a person resisting a request can file a motion for a protective order. This seeks to limit or prevent the discovery process. These mechanisms ensure that the exchange of information remains fair and organized. Without these rules, one side might hold all the facts, creating an unfair advantage during the trial.

The history of discovery began in the English Court of Chancery. This court used a system of equitable pleading. In the early thirteenth century, Italian communes used a practice called positiones. These were statements of evidence that a plaintiff assumed existed. The defendant had to respond by stating if these positions were true or false. This closely resembles modern requests for admissions. Between the reign of Elizabeth I (1558–1603) and the late seventeenth century, positiones were replaced by interrogatories. These were written questions that a defendant had to answer truthfully under oath. However, this early version was limited. It was a one-way process that only supported the plaintiff's case. A defendant had to file a cross-bill to ask their own questions.

A major innovation appeared in the mid-15th century to preserve testimony. This was a bill to perpetuate the testimony of potential witnesses. It was used for witnesses who were very old or in poor health. These people might not survive until the actual trial. In these proceedings, a subpoena ad testificandum was served at least 14 days in advance. In London, examinations happened before a master in Chancery Lane. Outside of London, attorneys appointed a group of lay commissioners to help. These were usually four country gentlemen who were not involved in the case. They were granted authority through a process called dedimus potestatem. A clerk would then write the witness's answers in a summary narrative form. This was not a verbatim transcript like a modern deposition.

These early depositions were fundamentally inquisitorial, meaning they were driven by the court. The proceedings were secret to prevent perjury or witness tampering. Witnesses testified from memory without seeing the parties or lawyers. This allowed for calm recollection and prevented mistakes caused by rapid cross-examination. In London, the resulting document was written on paper. Outside of London, the clerk engrossed the narrative on parchment. This document was filed under seal and kept secret until shortly before the trial. This method allowed the Lord Chancellor to use the record in place of live testimony. It was a way to build a factual record through a neutral, court-led process.

The system changed significantly in the 19th century. In the early 1800s, English settlers brought these traditions to the Thirteen Colonies. Chancellor James Kent of the New York Court of Chancery introduced major changes. He realized that written interrogatories led to long, complicated accounts. To fix this, he allowed masters to conduct oral examinations in real time. He also allowed lawyers to be present during these examinations. This meant the proceedings were no longer secret. These innovations spread to American federal practice in 1842. However, the presence of lawyers meant they often took control of the examination themselves.

Major reforms in the mid-1800s created the modern era of discovery. New York passed reforms in the late 1840s. England followed with similar reforms in the early 1850s. These laws separated pleadings from discovery as distinct phases. This meant discovery could be used independently of the initial legal claims. New York's code, brought by David Dudley Field II, even abolished written interrogatories. It merged common law and equity procedures. This allowed for the pretrial oral examination of both opposing parties and third-party witnesses. This evolution turned a secret, court-driven process into the interactive, party-driven system used in courts today.