ab initio （自始，例：void ab initio 自始无效）from the beginning

ad hoc （特别；特定；为某一目的特设，例：ah hoc committee 特设委员会；临时委员会；专门委员会）for this purpose

ad litem （专为某一诉讼目的；例：agent ad litem诉讼代理人）for the lawsuit

a fortiori （更加，更不必说） 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 （经验的；归纳的；后验的） from effect to cause; from particular to general; inductive (based on observation or experience).

a priori （先验的；演绎的） 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 （法庭之友） "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 （违反法律） "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 （事实；事实上） in fact (as opposed to in law, de jure)

de lege ferenda （根据拟议法） what the law ought to be (as opposed to what the law is, lex lata).

de lege lata （根据现行法）what the law is (as opposed to what the law ought to be, de lege ferenda).

de jure （法理上；法律上） in law (as opposed to in fact, de facto).

dolus specialis （特殊目的）special intent. In international humanitarian law, genocide is considered unique because of the special intent to destroy in whole or in part, a national, ethnic, racial or religious group.

erga omnes  （对所有国家；普遍适用；对国际社会整体。例：obligation erga omnes 对国际社会整体的义务；对世义务）"toward all" wrongful acts that harm everyone and not simply one injured party)

ex aequo et bono （根据公允及善意原则；本着公平与正义的精神） 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 proprio motu （出于自愿的；出自本意的） on its own accord.

ex proprio vigore （由于本身的力量）by its own strength / of its own force. A law or a treaty may be binding ex proprio vigore, or on its own. If an international law is not binding ex proprio vigore in domestic law, then legislative action is needed. A treaty that requires domestic legislation is referred to as a non-self-executing treaty.

forum conveniens （便利法庭；合适的裁判地）convenient forum. The court is convenient to hear a case and has jurisdiction. The doctrine of forum non conveniens ("inconvenient forum") allows a court to refurse to adjudicate a case on grounds of inconvenience.

forum non conveniens（不便利法庭；非方便裁判地） inconvenient forum.

in pari delicto （同等过错；互有过失）equally wrong. One party is as much at fault as the opposing party.

in pari materia （以相同方式）on like subject matter; same manner. typically used in regards to statutes which relate the same thing or person.

in personam （对人）against the person. Jurisdiction over the person of an individual.

in rem （对物） “in a thing”. In a lawsuit, an action in rem is directed towards some specific piece of property,

in statu nascendi （在新生状态/初始状态/原初状态中）in its original form / in birth status / being just born. Under international law, this term generally is used to refer to a nascent state or a political entity seeking recognition of statehood. It also is used to refer to emergent laws, rules, or principles of customary international law.

inter alia （在其他事项外；此外） among other things.

intra legem （法内） "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.

inter arma silent leges (战争的时候无法律可言；战时法律暂停生效) in time of war, the laws are silent

ipso facto （根据事实本身；事实使然） by the fact (or act) itself.

ipso jure （依照法律；根据法律）by the law itself

jus （法；权利）law or the body of law

jus ad bellum （诉诸战争权）Right to War. When and under what conditions is war ever justifiable? Jus ad bellum sets the boundaries for the use of force. War was denounced in the 1919 Covenant of the League of Nations and the 1928 Treaty of Paris (Briand-Kellogg Pact). The UN Charter adopted in 1945 states: "All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations." Article 2(4). The Charter authorizes the use of force in self defense. Article 51. See Chapter VII and Chapter VIII for more provisions. Compare jus ad bellum (right to use force) with jus in bello (conduct during war).

jus civile （市民法） law created within each country.  Jus civile is one of two categories of law in formal Roman law, along with jus gentium.

jus cogens （强制性法规；强制法；绝对法）"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 （万民法） "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 gentium privatum（国际私法）Private International Law

jus gentium publicum（国际公法）Public International Law

jus in bello（战时法）Justice in War. These principles govern the conduct of parties during the law of war and armed conflict, and in a broader sense define the rights and obligations of neutral parties. The basic legal frameworks include, but are not limited to: the 1907 Hague Conventions and Regulations; Geneva Conventions of 1949 and the 1977 Protocols I and II; the 1925 Geneva Gas Protocol; the 1954 Hague Cultural Property Convention; the 1972 Biological Weapons Convention; the 1980 Conventional Weapons Convention; and the 1993 Chemical Weapons Convention. See also jus ad bellum.

jus inter gentes （国家间法） "law among peoples" (nations).

jus naturale （自然法） 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 （血统主义；儿童国籍决定于父母国籍的惯例；根据血统决定国籍的原则）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 （出生地主义；儿童国籍决定于他的出生地的惯例；根据出生地决定国籍的原则） 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 （漏洞；“法律的间隙”） "holes" in the law; a gap or blank in a writing.

lex communis （普通法） the common law; the body of law developed by human practice.

lex ferenda （拟议法；应有法）what the law ought to be

lex lata （现有法律；现行法） what the law is

lex loci （所在地法）law of the place. The notion that the rights to a legal proceeding are governed by the law of the place where those rights arose.

lex posterior derogat priori （后法优于前法；孰后优先）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 mercatoria 商法

lex scripta （成文法） written, "black letter" law

lex specialis derogat generali （特别法优于一般法；特别法优先）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 （不法行为地；犯罪地）The place of the offense. male captus, bene detentus （以不恰当手段抓捕的罪犯可以合法拘押）"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"

malum in se （不法） inherently wrong. An act that is wrong by its nature, regardless of specific prohibition against it.

malum prohibitum （法律禁止的不法行为）prohibited, as by law. An act that is wrong because it is expressly prohibited by law.

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

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

mutatis mutandis （加以必要的变通；比照；参照） "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 （法律欠缺；不予裁决） the law is insufficient to provide a decision

nunc pro tunc （事后补正）now for then. Refers to actions that may be taken with retroactive effect.

opinio juris sive necessitatis （法律必要确信） (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 （有约必守） the doctrine that agreements must be observed (that is: honored, obeyed). Contrast to rebus sic stantibus.

per curiam （经由法庭；法院意见；法庭整体意见）by the court. An opinion written by the court with no identified author.

persona non grata （不受欢迎的人） An unwelcome person -- this is the basis of expulsion in diplomatic exchanges.

praetor peregrinus （外事裁判官）the Roman magistrate who devised the rules of the jus gentium

prima facie （初步，例：prima facie evidence初步证据） "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 （关于此事；单就这一点） on this matter.

ratio scripta （成文的理性） "written reason," the assessment of Roman law commonly held in the Medieval period

rebus sic stantibus （情事变更）  "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. Under Article 62 of the UN Vienna Convention on the Law of Treaties (VCLT), a party may be able to modify or terminate a treaty due to an unforeseeable and fundamental change of circumstances. This principle cannot be used for a treaty defining geographical boundaries and cannot be invoked as the result of a breach of a treaty. See the Gabcikovo-Nagymaros Project (Hungary v. Slovakia, ICJ)(applying Article 62).

res judicata （既判力） "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.

res communis （共有物）belonging to everyone / law of the commons. Typically used to refer to a territorial category for property and lands incapable of being owned, such as the high seas and outer space.

res judicata （已决事件；一事不再理原则）a thing decided. A common law doctrine holding that an adjudicated matter cannot be litigated again by another court.

res publica christiana （基督教共同体） the community of Christian nations.

sine qua non （绝对必需；必不可少的条件） "without which not," an indispensable condition, a prerequisite

stare decisis （遵循先例；判决拘束原则） 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 （无主地） land without an owner ("no man's land"); territory that may be acquired by a state's occupation of it. Typically used to refer to a territorial category for land that is not occupied but capable of being occupied.

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

uti possidetis （占有保持原则） "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 （或者不是） "or not "