Discovery, in the law of common law jurisdictions, is a phase of pretrial procedure in a lawsuit in which each party, through the law of civil procedure, can obtain evidence from other parties. This is by means of methods of discovery such as interrogatories, requests for production of documents, requests for admissions and depositions. Discovery can be obtained from nonparties using subpoenas. When a discovery request is objected to, the requesting party may seek the assistance of the court by filing a motion to compel discovery. Conversely, a party or nonparty resisting discovery can seek the assistance of the court by filing a motion for a protective order.
History Discovery evolved out of a unique feature of early equitable pleading procedure before the English Court of Chancery: among various requirements, a plaintiff's bill in equity was required to plead "positions". These were statements of evidence that the plaintiff assumed to exist in support of his pleading and which he believed lay within the knowledge of the defendant. They strongly resembled modern requests for admissions, in that the defendant was required to plead only whether they were true or false. Available through HeinOnline. The practice of pleading positiones in canon law (which influenced Chancery procedure) had originated with "the practice of the courts of the Italian communes in the early thirteenth century". Although canonists also looked to Roman law, positiones were unknown to the Romans.
At some point between the reign of Elizabeth I (1558–1603) and the late seventeenth century, positions were gradually replaced by interrogatories: written questions which the defendant was required to truthfully respond to under oath in his answer to the bill, based on information within his own personal knowledge as well as documents in his possession. But back then, interrogatories could only elicit admissible evidence (not the broader modern standard of "reasonably calculated to lead to the discovery of admissible evidence") and could only request evidence in support of the plaintiff's case, not either side's case (that is, they could not ask for evidence which the defendant intended to use in support of his defenses and was otherwise entirely irrelevant to the plaintiff's case). Even worse, this was purely a one-way procedure, because interrogatories could only be pleaded as part of a bill (a pleading initiating a suit in equity). A defendant who needed to obtain evidence in support of his defenses had to file a cross-bill against the plaintiff to plead his own interrogatories.
Discovery did not exist at common law, but its availability in equity attracted litigants in actions at law (legal proceedings in the common law courts). They began to file bills in equity to obtain discovery in aid of actions at law. This led to another innovation in the mid-15th century: the bill to perpetuate testimony of a potential witness. This was for witnesses whose advanced age or poor health implied they would not survive to testify at the trial of an action at law.
In this type of proceeding, the parties merely pleaded written interrogatories which were read out loud to the witness in a closed proceeding without parties or counsel present. The witness's attendance was secured by service of a subpoena ad testificandum at least 14 days before the date of the examination. In London, the examinations took place before a master or an examiner in Chancery Lane. Outside of London, the parties' attorneys were supposed to jointly stipulate to a group of lay commissioners (typically four, though only two were needed for a quorum) who could not be interested persons (i.e., parties or their lawyers) and were usually country gentlemen. Once agreed upon, the court would grant them authority to examine witnesses by way of dedimus potestatem.
The person(s) examining the witness would appoint a clerk, whom under their supervision would write down the witness's oral answers under oath in summary form on paper, as if they had been spontaneously delivered as a single continuous third-person narrative, rather than as responses given in the first person to discrete questions. At p. 86. Available through SpringerLink. In other words, the actual sequence of questions and answers was not transcribed verbatim like a modern deposition. For example, the surviving narratives of multiple witnesses to a 16 May 1643 enclosure riot in Whittlesey reveal striking similarities which imply the witnesses probably gave "yes" and "no" answers to the same set of interrogatories. At p. 87. Available through SpringerLink. In London, the witness usually signed or marked the narrative at its end (and occasionally would sign at the bottom of each page), while outside of London, the clerk engrossed the narrative on parchment (in plain English, copied the text from paper to parchment in clearly legible handwriting). At p. 85. Available through SpringerLink. Either way, the resulting document (paper in or near London, parchment outside London) was filed under seal with the court, and was not revealed or "published" (in the terminology of the time) to parties or counsel until shortly before the trial in which it was to be used. An 1899 treatise on evidence law explained the rationale for this method of examining a witness in equity: it allowed a witness "ample time" for "calm recollection" as they answered questions read by a neutral person and an opportunity to correct the record at the end before it was submitted to the court as evidence. In contrast, at trial in a common law court, the witness might be subject to "severe and rapid cross-examination" without sufficient time for reflection or deliberation, thereby causing them to "misrepresent facts, from infirmity of recollection or mistake".
This procedure for ex parte out-of-court pretrial examinations under the authority of courts of equity came to be called a "deposition". It continued to be used as an evidence preservation device in aid of actions at law, but it also became the standard method for developing the factual record to be used in courts of equity as derived from the knowledge of third-party witnesses (not merely those who were old or dying). The process of summarizing testimony in narrative form, to be relied upon by the Lord Chancellor in lieu of live testimony in open court, was a kind of factfinding process in its own right. As implied by the secret nature of the proceedings and the absence of parties and counsel, equity's factfinding process was fundamentally inquisitorial (i.e., driven by the court), and not adversarial (i.e., driven by the parties). It is generally believed that this came about because the early Chancellors and the masters who assisted them were clerics with training in Roman and canon law, and therefore had some knowledge of the inquisitorial system as it functioned in ecclesiastical courts. The secrecy was thought to be absolutely essential to prevent perjury and witness tampering; the witnesses would thereby be forced to testify from memory alone, and the parties could not use the facts disclosed in testimony to guide their discovery or litigation strategy. Consistent with these inquisitorial views, there were also prohibitions on repeat testimony and on additional testimony after publication. Rather, the witnesses would testify independently of each other before publication, then at the moment of publication, all would be revealed, and the parties would make their arguments to the Chancellor on that cold record.
One key difference, however, was that in ecclesiastical courts, the judge himself took the depositions of the witnesses (by reading to them the interrogatories submitted by the parties), and thus personally developed the factual record which the parties would then argue over at trial. To modern eyes, the most bizarre aspect of Chancery's adoption of such a labor-intensive quasi-inquisitorial procedure was that for most of its history, Chancery was a one-judge court. The Crown always attempted to operate the judiciary of England and Wales as cheaply as possible—by leaving it severely understaffed in comparison to its counterparts on the European continent—thereby leaving the chancellors no choice but to delegate factfinding procedures like the taking of depositions.
Despite these defects, English settlers brought discovery and depositions with them to the Thirteen Colonies, including the tradition of having courts of equity appoint masters to take depositions. It is this quasi-inquisitorial procedure to which the United States Congress was referring in an 1802 law providing that "in all suits in equity, it shall be in the discretion of the court, upon the request of either party, to order the testimony of the witnesses therein to be taken by depositions."An Act to Amend the Judicial System of the United States, ch. 31, § 25, 2 Stat. 156, 166 (1802).
The next major development (which would remain a unique feature of American and Canadian discovery) occurred under the supervision of Chancellor James Kent of the New York Court of Chancery during the early 19th century. He was trying to respond to the obvious defect of traditional depositions: since parties could not adjust their questions on the fly, they had to propound broadly drawn interrogatories, and in turn elicited "long and complicated accounts" of the facts that were difficult for masters to summarize in writing. Therefore, Kent allowed New York masters to actively engage in oral examination of witnesses (in the sense of formulating questions in real time and narrowing their scope based on the witnesses' answers), and he also allowed parties and counsel to be present when such examinations were conducted. Kent's innovations spread into American federal practice in 1842 when the U.S. Supreme Court amended the Federal Equity Rules to allow masters in equity suits in federal courts to conduct oral examinations of witnesses.
However, with the parties and counsel now present to help guide the course of the master's oral examination of the witness, it was inevitable that counsel would insist on taking over the examination itself, and their presence meant the proceedings were no longer secret. A New York deposition from January 1839 reveals that the examiner had already lost control of the examination. The examiner was reduced to summarizing a flurry of objections and arguments exchanged between the lawyers after one of them allegedly tried to take the witness aside to get an informal preview of the witness's answers before getting them on the record. All this would have been impossible under the old deposition procedure where counsel was not present.
Major reforms enacted in New York in the late 1840s and in England in the early 1850s laid the foundation for the rise of modern discovery by imposing a clear separation between pleadings and discovery as distinct phases of procedural law. Discovery devices could now be invoked independently of the pleadings. The New York reforms went much farther, by directly merging common law and equity procedure (which would also happen in England in the early 1870s), and by expressly authorizing pretrial oral examinations of both opposing parties and third-party witnesses, the basis of the modern deposition. (Up to that point, discovery from able-bodied opposing parties was still limited to interrogatories.) In fact, the New York code of civil procedure (brought about by David Dudley Field II) went so far as to abolish written interrogatories. A major flaw, though, of the New York code of civil procedure was that it only allowed parties to seek discovery on issues on which they would have the burden of proof at trial. This caused lawyers for defendants to plead fictional defenses in answers, because they still could not directly pursue discovery into the plaintiff's claims.