Definition
In international law, reprisals are coercive measures taken by one nation against another in response to an injury, wrong, or violation of law committed by the latter. The defining feature is proportionality and purpose: reprisals are not acts of war but rather forcible self-help short of war, intended to compel redress or satisfaction. Historically, the term encompassed the seizure of persons, ships, or property belonging to the offending state or its nationals.
Two principal forms appear in classic legal usage:
1. General reprisals: Authorized by a government through commissions issued to officers and private citizens, empowering them broadly to seize the persons and property of the offending nation wherever found. General reprisals shade into — and historically preceded — formal declarations of war.
2. Special reprisals: Limited authorizations to a specific injured party to recover a specific wrong, typically by seizing equivalent property of the offending nation's subjects. Special reprisals were the earlier and more narrowly targeted form.
In modern usage, the term has expanded beyond the international-law context. In domestic employment and administrative law, reprisal refers to adverse action taken against an individual (employee, whistleblower, complainant) in retaliation for a protected activity. This usage is legally distinct from the international-law sense and governed by entirely different bodies of law.
Common Language
Modern common usage (Wiktionary): Plural of reprisal — an act of retaliation.
Historical common usage (Webster's 1913): An act of retaliation, especially the seizure of goods or persons in retaliation for injury.
The common and legal meanings share a root in retaliation, but the legal meanings diverge in two important directions. In international law, reprisals are a formally defined category of state action with procedural requirements, proportionality constraints, and treaty-law implications — not mere informal retaliation. In domestic employment and administrative law, reprisal is a term of art describing unlawful employer conduct against protected activities, a meaning entirely absent from ordinary usage.
Recognized Forms
/SUBTYPES
General Reprisals: Government-issued commissions authorizing broad seizure of the offending nation's persons and property. Functionally close to — and often a prelude to — a state of war.
Special Reprisals: Narrow authorizations granted to a specific injured party to seize property of the offending state's subjects, equivalent in value to the injury suffered. The historically earlier form, associated with private redress.
Negative Reprisals: A state refuses to fulfill an existing obligation to the offending state — a form of withholding rather than seizure.
Positive Reprisals: Active seizure of the subjects or property of the offending state in response to injury.
Retorsion (distinguished): A related but distinct concept — unfriendly acts that are nevertheless lawful, employed in response to another state's unfriendly or unlawful acts. Rapalje & Lawrence treat retorsion as falling within the broader category of measures reprisals encompass; Vattel and later international law keep the terms formally separate.
Why It Matters in Research
Researchers face three significant traps with this term.
First, the historical international-law meaning and the modern domestic-law meaning coexist in the corpus but are governed by entirely separate legal frameworks. A search for reprisals in early American sources will almost exclusively return the international-law sense — seizing enemy property, letters of marque, prize law. The domestic employment-law usage (retaliation against whistleblowers or civil rights complainants) does not appear in historical sources under this term and is indexed differently in modern sources.
Second, the relationship between reprisals and war is a live research question in older materials. General reprisals, in historical doctrine, were understood to be a step on a recognized escalation ladder: special reprisals → general reprisals → war. Researchers working in sources from the founding era through the 19th century will find reprisals treated as a quasi-formal intermediate state with recognized legal consequences for neutrals, prize courts, and maritime insurance — not simply as informal retaliation.
Third, the term appears in U.S. constitutional history in connection with the Marque and Reprisal Clause (Article I, Section 8), which grants Congress the power to grant letters of marque and reprisal. Sources discussing this clause use reprisal in the strict international-law sense of authorized seizure. Researchers conflating this with modern domestic usage of the term will misread the constitutional materials.
The corpus connection between reprisals and prize law is strong and underutilized: 18th- and 19th-century prize court decisions frequently turn on whether reprisals had been properly authorized and whether the seizure was proportionate to the original injury.
Historical Dictionary Support
Black's Law Dictionary (both editions) and Bouvier's give nearly identical definitions, all tracing to Vattel's Law of Nations (Book II, Chapter 18, Section 342) as the canonical source. This uniformity reflects how thoroughly 19th-century American legal dictionaries relied on Vattel for public international law — a researcher should treat these dictionary definitions as restatements of Vattelian doctrine rather than independent American legal developments.
Rapalje & Lawrence is the most analytically useful of the historical sources, offering the negative/positive distinction and explicitly situating reprisals within the spectrum of coercive measures short of war. This entry also flags the relationship to embargo and retorsion — connections the Black's and Bouvier's entries omit.
What all historical sources miss: the modern domestic-law usage of reprisal as unlawful employer retaliation. This meaning is entirely post-20th century in its legal development and will not appear in any of the shelf sources.
Jurisdictional Note
In international law, the legality of reprisals as a state remedy has been substantially curtailed by the UN Charter framework, which restricts unilateral forcible measures between states. In U.S. domestic law, the term reprisal is used in federal whistleblower statutes and administrative law to describe prohibited retaliation, with the specific definition and enforcement mechanisms varying by statute and agency.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: War Powers and the Marque and Reprisal Clause; Prize Law and Maritime Seizure; International Law in Early American Courts.