Definition
A court of oyer and terminer (from the Anglo-French "to hear and determine") is a criminal tribunal historically empowered to hear and decide serious criminal cases, particularly felonies and capital offenses. The name describes the court's essential function: to receive charges and render final judgment upon them.
In English practice, the court operated through royal commissions issued to judges authorizing them to hear and determine criminal matters at assizes. The commission of oyer and terminer was one of several commissions carried by assize judges on circuit, alongside the commission of general gaol delivery. Together, these commissions ensured that prisoners held in county gaols received trial rather than indefinite detention.
In American practice, courts of oyer and terminer functioned as superior criminal courts of record with jurisdiction over serious offenses — felonies, capital cases, and matters beyond the competence of lower courts. Their specific powers, composition, and procedures varied considerably by state.
Common Confusion
COURT OF OYER AND TERMINER / COMMISSION OF OYER AND TERMINER: In English practice, the distinction between the court and the commission matters. The commission was the royal instrument authorizing certain judges or commissioners to act; the court was the tribunal constituted when those commissioners sat. Historical sources sometimes use the terms interchangeably, which can obscure whether a source is describing the authorizing instrument or the sitting tribunal. In American usage, "court of oyer and terminer" almost always refers to a standing court, not an ad hoc commission.
COURT OF OYER AND TERMINER / COURT OF GENERAL JAIL DELIVERY: These courts are closely linked — in English practice they were often held together under combined commissions — but they are distinct. The court of oyer and terminer heard and determined charges. The court of general gaol (jail) delivery cleared the gaol of all prisoners awaiting trial, whether or not previously indicted. Black's Law Dictionary groups them together under a single heading, reflecting their historical overlap, but they are formally separate institutions. Researchers who find reference to one should check for the other in the same source.
Recognized Forms
/SUBTYPES
General Commission of Oyer and Terminer: Authorized hearing of all treasons, felonies, and misdemeanors within a specified territory. The broadest form of the commission.
Special Commission of Oyer and Terminer: Issued for a particular case or class of cases, often in response to a specific emergency or notorious offense. Used in England when the Crown wished to accelerate trial outside the regular assize schedule.
American State Courts of Oyer and Terminer: Standing courts bearing the traditional name but operating under statutory rather than commission authority. Pennsylvania and Delaware are the clearest American survivals of the institution.
Why It Matters in Research
The term appears across a very wide chronological range — from medieval English sources through late nineteenth-century American statutes — and its meaning shifts substantially across that span. A researcher encountering "oyer and terminer" in a seventeenth-century English document is reading about a commission; the same phrase in an 1850 Pennsylvania case reporter refers to a standing state court with defined statutory jurisdiction. Conflating the two will produce errors in understanding both procedure and authority.
The abolition dates matter. New York abolished its court of oyer and terminer on December 31, 1895. New Jersey abolished its by acts of March 14 and 22, 1895. Cases decided in those states before those dates may have traveled through an oyer and terminer court; cases after will not. Researchers tracing New York or New Jersey criminal procedure in the late nineteenth century should treat 1895 as a jurisdictional fault line.
In Pennsylvania, the court of oyer and terminer historically sat simultaneously with the court of quarter sessions and was presided over by the same judges. This means that Pennsylvania primary sources — dockets, reports, session records — may interleave proceedings from both courts, and distinguishing between them requires attention to the specific matter being tried rather than the caption alone.
The Salem witch trials of 1692 were conducted before a specially constituted court of oyer and terminer, making the term familiar in American legal history far outside its normal criminal-procedure context. Researchers should be alert to this association when the term appears in materials touching that period and episode.
Because Black's Law Dictionary's entry for this court is grouped with general jail delivery, researchers using that source should read both entries together to get a complete picture of how English assize courts functioned.
Historical Dictionary Support
Bouvier's Law Dictionary provides the more useful American-practice account of the two shelf sources here. Bouvier confirms the term's survival in Delaware and Pennsylvania, supplies the specific abolition dates for New York and New Jersey, and notes the Pennsylvania practice of holding oyer and terminer simultaneously with the court of quarter sessions. This is genuinely useful navigational information for a researcher working in those jurisdictions.
Black's entry, as available here, groups the court with general jail delivery — a defensible editorial choice given how closely the two commissions operated in English practice, but one that can obscure the formal distinction between them. Neither shelf source provides substantial treatment of the English commission framework that underlies the American institution. Researchers needing that background must go to English legal history sources beyond the standard American dictionaries.
Both sources are silent on the special commissions issued for particular emergencies or notorious cases, which were historically significant and appear with some frequency in English state trial reports.
Jurisdictional Note
The court survived longest as a named institution in Pennsylvania and Delaware. In most American jurisdictions, the functions of oyer and terminer were absorbed into general superior criminal courts during nineteenth-century court reorganizations, often without explicit abolition — the institution simply ceased to be separately named. Researchers working in states other than Pennsylvania, Delaware, New York, and New Jersey should not assume a formally constituted oyer and terminer court existed in their jurisdiction simply because the phrase appears in a document; it may refer to a commission, a court sitting in a particular capacity, or a borrowed term used loosely.