"Beck's Law Dictionary": A Compendium of International Law Terms and Phrases


Black's Law Dictionary is the best source for most legal terms and phrases. If you intend to attend law school, I recommend that you purchase a copy of this classic reference text.

Nota bene: In general, the translations provided here are contextual rather than strictly literal.



a fortiori - according to Webster: "with greater reason or more convincing force -- used in drawing a conclusion that is inferred to be even more certain than another."

Example: If it is a violation of the sending state's rights to arrest its consular official, then a fortiori it would be a violation to arrest its ambassador.

a posteriori - from effect to cause; from particular to general; inductive (based on observation or experience).

a priori - from cause to effect; from generalization to particular; deductive; presupposed by or reasoning from self-evident propositions (based on theory rather than practice).

amicus curiae - "friend of the court"; a person with a strong interest in or views on the subject matter of a given legal action may petition the court for permission to file a brief, ostensibly on behalf of a party but actually to suggest a rationale consistent with its own views. Such amicus curiae briefs are commonly filed in appeals concerning matters of a broad public interest.

Example: NPC of Iran v. M/T Stolt Sheaf case

contra legem - "against the law" (term used to describe an equitable decision of a court or tribunal that is contrary to the law governing the controversy.  Such a decision would not normally be permitted unless the tribunal had been empowered to act ex aequo et bono).  As opposed to intra legem.

de facto - in fact (as opposed to in law, de jure)

de lege ferenda - what the law ought to be (as opposed to what the law is, lex lata).

de lege lata - what the law is (as opposed to what the law ought to be, de lege ferenda).

de jure - in law (as opposed to in fact, de facto).

erga omnes - "toward all" wrongful acts that harm everyone and not simply one injured party)

estoppel - the requirement of consistency in legal argumentation. "You can't have it both ways."  That is:  "You can't have your cake and eat it, too."

Hypothetical example: Party A cannot claim a right from Party B if Party A previously took actions or made statements that were contrary to the current claims and which led Party B to take an action that is the subject of the current claim.

Case illustrations: the Tinoco Claims Arbitration and the Eastern Greenland case

ex aequo et bono - a judgment based on considerations of fairness, not on considerations of existing law. Such a judgment is rendered "beside" or "against the law" (praeter legem or contra legem), not within the law (infra legem or intra legem).

Example: Article 38(2) of the I.C.J. Statute permits the Court to render a judgment on these grounds

ex propio motu - on its own accord.

inter alia - among other things.

intra fauces terra - "in the jaws of the land." a principle for defining territorial seas.

intra legem - "within the law" (term used to describe an equitable decision of a court or tribunal that is consistent with the rules of law governing the controversy).  As opposed to contra legem.

ipso facto - by the fact (or act) itself.

jus inter gentes - "law among peoples" (nations).

jus civile - law created within each country.

Jus civile is one of two categories of law in formal Roman law, along with jus gentium.

jus cogens - "compelling law," peremptory principles of international law that cannot be overriden by specific treaties between countries; that is: norms that admit of no derogation; they are binding on all states at all times (e.g., prohibitions on aggression, slavery, and genocide)..

jus gentium - "law of peoples" or "law of tribes,"  a body of law developed by a Roman praetor peregrinus; applied to non-Romans in the Empire and to dealings between Romans and non-Romans.

Jus gentium is one of two categories of law in formal Roman law, along with jus civile.

jus naturale - law of nature.

the classical Greeks originated the "natural law" idea, but it was greatly elaborated upon by the Romans, including Marcus Aurelius and Cicero; natural law scholars argue that law has a metaphysical source (God, nature) and is apprehensible by rational humans; the law transcends tiem, place, and circumstance

jus sanguines - the "right of blood" or "law of descent" -  at birth an individual acquires the nationality of her or his parents.  In contrast to jus soli.

jus soli - the "law (or right) of the soil" - the legal principle that an individual's nationality is determined by that person's place of birth (that is, the territory of a given state)

Contrast to jus sanguines

lacunae - "holes" in the law; a gap or blank in a writing.

lex communis - the common law; the body of law developed by human practice.

lex lata - what the law is (as opposed to what the law ought to be, de lege ferenda).

lex posterior derogat priori - more recent law prevails over (abrogrates, overrrules, trumps) an inconsistent earlier law. One test that is applied in circumstances when (1) both customary and treaty sources of law exist and (2) these two sources cannot be construed consistently.

Contrast to lex specialis derogat generali .

lex scripta - written, "black letter" law

lex specialis derogat generali - specific law prevails over (abrogrates, overrrules, trumps) general law. One test that is applied in circumstances when (1) both customary and treaty sources of law exist and (2) these two sources cannot be construed consistently.

Contrast to lex posterior derogat priori.

locus delicti - The place of the offense.

male captus, bene detentus - "badly captured, well detained," the legal principle that permits the trial of an improperly seized defendant; in U.S. practice, articulated by the "Ker-Frisbie doctrine"

mare clausum - closed seas; as opposed to mare liberum (freedom of the seas)

mare liberum - freedom of the seas; as opposed to mare clausum (closed seas)

mesne assignment - an "assignment" is a transfer or making over to another of the whole of any property, real or personal, or of any estate or right therein; a "mesne assignment" (from the Old English "mesne" for "intermediate, intervening")  is an assignment intervening between an original grant and the last assignment

See:  Upright v. Mercury Business Machines

mutatis mutandis - "when what must be changed has been changed," after making the necessary changes; with alterations to fit the new circumstances.  For example:  "The new provisions governing the tribunal's operations are to apply as well to the court's operations, mutatis mutandis.

non liquet - the law is insufficient to provide a decision

opinio juris sive necessitatis - (or simply, opinio juris) the perception that a given behavior is required by law, that it is legally obliged, a duty. (as opposed to behaviors that are motivated by other concerns, or simply random or habitual behavior).

Example: the S.S. Lotus case.

pacta sunt servanda - the doctrine that agreements must be observed (that is:  honored, obeyed).

Contrast to rebus sic stantibus.

persona non grata - An unwelcome person -- this is the basis of expulsion in diplomatic exchanges.

praetor peregrinus - the Roman magistrate who devised the rules of the jus gentium

prima facie -  "at first sight," on the face of it, on first consideration. Something presumed or inferred to be true, unless proven otherwise. The standard of evidence applied at U.S. extradition hearings.

quod hoc - on this matter.

ratio scripta - "written reason," the assessment of Roman law commonly held in the Medieval period

rebus sic stantibus -  "matters standing thus,"  "things staying as they are" - the doctrine that treaty obligations hold only as long as the fundamental conditions and expectations that existed at the time of their creation hold.

Contrast to pacta sunt servanda.

res judicata - "a matter adjudged ", the legal principle common to many municipal law systems that provides that a matter is settled once a final judgment has been made. Arguably, a general principle of international law under Article 38 (1)(c) of the I.C.J. Statute.

sine qua non - "without which not," an indispensable condition, a prerequisite

res publica christiana - the community of Christian nations.

stare decisis - The doctrine that previous court decisions establish binding precedent for future cases of similar situations; that is, that courts will abide by previously decided cases.  Stare decisis is inapplicable to the I.C.J..

See article 59 of the Statute of the ICJ.

terra nullius - land without an owner ("no man's land"); territory that may be acquired by a state's occupation of it

ultra vires - "beyond the powers "; in excess of the authority conferred by law, and hence, invalid, lacking legal effect

uti possidetis - "as you possess", so you may continue to possess

in the post-war context:  the concept that a state may retain possession of territory acquired by force during war 

in the post-colonial context:  the concept that colonial territorial boundaries continue in the post-colonial period and that decolonized territories are not terra nullius (and thus, subject to occupation)    See, for example, Burkina Faso v. Mali

vel non - "or not "


 

Updated: June 23, 1999


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This compendium draws upon those originally compiled by Professors Kurt Taylor Gaubatz and Robert Turner.