Definition
Prosecution has three related but distinct legal meanings:
1. The formal proceeding. A criminal prosecution is the formal legal process initiated by the government — through a prosecutor acting on behalf of the state — before a competent tribunal, for the purpose of determining the guilt or innocence of a person charged with a crime. It encompasses everything from the filing of charges through the final disposition of the case.
2. The party. "The prosecution" refers collectively to the government as the moving party in a criminal proceeding — the state, sovereign, or public body, acting through its attorneys and agents in opposition to the defendant. When a courtroom reference is made to what "the prosecution argues," this meaning is in play.
3. The act of pursuing any legal proceeding. In a broader procedural sense, prosecution includes the carrying on of any civil or criminal judicial proceeding on behalf of a complaining party, as distinguished from the defense. A civil plaintiff "prosecutes" a claim; a relator "prosecutes" a qui tam action. This usage is older and less common in modern American legal writing but appears throughout historical records.
Common Language
Modern common usage (Wiktionary): The act of prosecuting a scheme or endeavor; the institution of legal proceedings, particularly criminal, against a person; the prosecuting party.
Historical common usage (Webster's 1913): "The act or process of prosecuting, or of endeavoring to gain or accomplish something; pursuit by efforts of body or mind; as, the prosecution of a scheme, plan, design, or undertaking; the prosecution of war."
The everyday English sense — pursuing any goal or endeavor with effort — is broad enough to encompass legal proceedings, which creates no dramatic gap. However, the legal meaning narrows sharply in two directions: in modern American law, prosecution almost always signals a criminal proceeding brought by the government, not a civil action and not private effort. Researchers encountering the word in older statutes, treatises, or common law records should resist the assumption that it refers only to criminal proceedings; the historical procedural sense covered civil actions as well.
Common Confusion
Prosecution is sometimes conflated with investigation. An investigation precedes prosecution; charges need not have been filed and no tribunal need be involved. Prosecution begins at the point of formal legal proceedings, not at arrest or grand jury inquiry. This distinction matters in Fourth and Fifth Amendment research, where constitutional protections attach differently depending on whether the proceeding has reached the prosecutorial stage.
Prosecution should also be distinguished from indictment, which is a specific charging instrument, not the entire proceeding. An indictment initiates prosecution but is not synonymous with it.
Why It Matters in Research
The tri-part meaning of prosecution creates real traps. In equity records and older common law sources, you will encounter prosecution used for civil proceedings — a party "prosecuting" a bill in chancery, or "prosecuting" a writ. Treating all such instances as criminal references will skew your research. The narrowing of prosecution to mean predominantly criminal government action is largely a nineteenth- and twentieth-century development.
In constitutional research, the word carries significant weight in double jeopardy doctrine, the Speedy Trial Clause, and prosecutorial discretion cases. Courts distinguish between the commencement, suspension, and termination of prosecution, and each marker triggers different rights. Historical sources use these markers inconsistently, so pay close attention to procedural posture when reading older decisions.
For administrative and regulatory research, the term reappears in a quasi-criminal context: agency enforcement actions are sometimes described as prosecutions and the enforcement arm of an agency as its "prosecution" division. This usage is functional rather than strictly legal and does not carry all the constitutional protections of a formal criminal prosecution — a distinction courts have been careful to maintain.
When the government is the defendant — as in sovereign immunity questions — the phrase "criminal prosecution of government actors" highlights the unusual posture where constitutional limitations on prosecution interact with immunity doctrines. The Law Mind Criminal Law Encyclopedia entry on sovereign immunity addresses this directly.
Corpus searches for "prosecution" in historical databases will return high noise from the general English sense. Filtering by context words (tribunal, indictment, criminal, defendant) improves precision considerably.
Historical Dictionary Support
Black's Law Dictionary (1st and 2nd editions) agree closely, defining prosecution as a criminal action before a competent tribunal for determining guilt or innocence, while noting the extended usage applying "prosecution" to the state or its counsel as a party. Both editions anchor the term firmly in criminal procedure.
Burrill's Law Dictionary provides the richest historical layering, moving from the general practice sense ("following up a judicial proceeding") to the intermediate sense (carrying on proceedings on behalf of a complaining party, as opposed to defense), and finally to the strictest criminal sense. Burrill explicitly notes the Latin root prosecutio and the connection to prosequi — to follow up — which explains why the word historically applied to any party actively carrying a proceeding forward, civil or criminal. His reference to Blackstone's Commentaries (4 Bl. Com. 301) places the criminal usage within the classical common law framework.
Anderson's Dictionary of Law does not provide a useful entry for this term; the retrieved text is a mismatch (discussing "proprietors" of a railroad) and should not be relied upon.
The historical dictionaries collectively underrepresent the institutional dimension of prosecution — the organized office of the prosecutor, the discretionary authority of the state to decline prosecution, and the constitutional constraints on prosecutorial conduct. These developments postdate the major dictionary editions and must be traced through case law and treatises rather than historical lexicography.
Jurisdictional Note
In the federal system and most states, criminal prosecution is exclusively a government function. A handful of states retain statutory provisions allowing private prosecution in limited circumstances, though these are increasingly disfavored. In England and some Commonwealth jurisdictions, private prosecution remains a recognized right, which affects how translated or comparative sources use the term.
Encyclopedia Cross-Reference
Sovereign Immunity and Criminal Prosecution of Government Actors — Law Mind Criminal Law Encyclopedia
Environmental Enforcement — Citizen Suits, Penalties, and Criminal Prosecution — Law Mind Administrative Law & Government Encyclopedia
Domestic Violence — Criminal Prosecution of Domestic Violence Offenses — Law Mind Family Law Encyclopedia