law Law is a set of rules that are created and are enforceable by social or governmental institutions to regulate behavior,Robertson, ''Crimes against humanity'', 90. with its precise definition a matter of longstanding debate. It has been vario ...

, (

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

for "

ignorance Ignorance is a lack of knowledge and understanding. The word "ignorant" is an adjective that describes a person in the state of being unaware, or even cognitive dissonance and other cognitive relation, and can describe individuals who are unaware o ...

of the law excuses not"),''

Black's Law Dictionary ''Black's Law Dictionary'' is the most frequently used legal dictionary in the United States. Henry Campbell Black (1860–1927) was the author of the first two editions of the dictionary. History The first edition was published in 1891 by West P ...

'', 5th Edition, pg. 672 or ("ignorance of law excuses no one"),''

'', 5th Edition, pg. 673 is a

legal principle A legal doctrine is a framework, set of rules, procedural steps, or test, often established through precedent in the common law, through which judgments can be determined in a given legal case. A doctrine comes about when a judge makes a ruling ...

holding that a person who is unaware of a law may not escape liability for violating that law merely by being unaware of its content. European-law countries with a tradition of

Roman law Roman law is the law, legal system of ancient Rome, including the legal developments spanning over a thousand years of jurisprudence, from the Twelve Tables (c. 449 BC), to the ''Corpus Juris Civilis'' (AD 529) ordered by Eastern Roman emperor J ...

may also use an expression from

Aristotle Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...

translated into Latin: ("nobody is thought to be ignorant of the law") or ("not knowing the law is harmful").

Explanation

The rationale of the doctrine is that if ignorance were an excuse, a person charged with

criminal offense In ordinary language, a crime is an unlawful act punishable by a state or other authority. The term ''crime'' does not, in modern criminal law, have any simple and universally accepted definition,Farmer, Lindsay: "Crime, definitions of", in Can ...

s or a subject of a civil

lawsuit - A lawsuit is a proceeding by a party or parties against another in the civil court of law. The archaic term "suit in law" is found in only a small number of laws still in effect today. The term "lawsuit" is used in reference to a civil actio ...

would merely claim that one was unaware of the law in question to avoid liability, even if that person really does know what the law in question is. Thus, the law imputes knowledge of all laws to all persons within the

jurisdiction Jurisdiction (from Latin 'law' + 'declaration') is the legal term for the legal authority granted to a legal entity to enact justice. In federations like the United States, areas of jurisdiction apply to local, state, and federal levels. Jur ...

no matter how transiently. Even though it would be impossible, even for someone with substantial legal training, to be aware of every law in operation in every aspect of a state's activities, this is the price paid to ensure that

willful blindness Willful blindness is a term used in law to describe a situation in which a person seeks to avoid civil or criminal liability for a wrongful act by intentionally keeping themselves unaware of facts that would render them liable or implicated. In ' ...

cannot become the basis of

exculpation In jurisprudence, an excuse is a defense to criminal charges that is distinct from an exculpation. Justification and excuse are different defenses in a criminal case (See Justification and excuse).Criminal Law Cases and Materials, 7th ed. 20 ...

. Thus, it is well settled that persons engaged in any undertakings outside what is common for a normal person will make themselves aware of the laws necessary to engage in that undertaking. If they do not, they cannot complain if they incur liability. The doctrine assumes that the law in question has been properly promulgated—published and distributed, for example, by being printed in a

government gazette A government gazette (also known as an official gazette, official journal, official newspaper, official monitor or official bulletin) is a periodical publication that has been authorised to publish public or legal notices. It is usually establis ...

, made available over the

Internet The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, pub ...

, or printed in volumes available for sale to the public at affordable prices. In the ancient phrase of

Gratian Gratian (; la, Gratianus; 18 April 359 – 25 August 383) was emperor of the Western Roman Empire from 367 to 383. The eldest son of Valentinian I, Gratian accompanied his father on several campaigns along the Rhine and Danube frontiers and wa ...

, ''Leges instituuntur cum promulgantur'' ("

Laws Law is a set of rules that are created and are law enforcement, enforceable by social or governmental institutions to regulate behavior,Robertson, ''Crimes against humanity'', 90. with its precise definition a matter of longstanding debate. ...

are instituted when they are promulgated"). In order that a law obtain the binding force which is proper to a law, it must be applied to the men who have to be ruled by it. Such application is made by their being given notice by promulgation. A law can bind only when it is reasonably possible for those to whom it applies to acquire knowledge of it in order to observe it, even if actual knowledge of the law is absent for a particular individual. A secret law is no law at all. In

criminal law Criminal law is the body of law that relates to crime. It prescribes conduct perceived as threatening, harmful, or otherwise endangering to the property, health, safety, and moral welfare of people inclusive of one's self. Most criminal law i ...

, although ignorance may not clear a defendant of

guilt Guilt may refer to: *Guilt (emotion), an emotion that occurs when a person feels that they have violated a moral standard *Culpability, a legal term *Guilt (law), a legal term Music * ''Guilt'' (album), a 2009 album by Mims * "Guilt" (The Long Bl ...

, it can be a consideration in

sentencing In law, a sentence is the punishment for a crime ordered by a trial court after conviction in a criminal procedure, normally at the conclusion of a trial. A sentence may consist of imprisonment, a fine, or other sanctions. Sentences for mult ...

, particularly where the law is unclear or the defendant sought advice from law enforcement or regulatory officials. For example, in one

Canadian Canadians (french: Canadiens) are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of ...

case, a person was charged with being in possession of

gambling Gambling (also known as betting or gaming) is the wagering of something of value ("the stakes") on a random event with the intent of winning something else of value, where instances of strategy are discounted. Gambling thus requires three el ...

devices after they had been advised by

customs Customs is an authority or agency in a country responsible for collecting tariffs and for controlling the flow of goods, including animals, transports, personal effects, and hazardous items, into and out of a country. Traditionally, customs ...

officials that it was legal to import such devices into Canada. Although the defendant was convicted, the sentence was an absolute discharge. In addition, there were, particularly in the days before

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope ...

communication and

cellular phones A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive calls over a radio frequency link while ...

, persons who could genuinely be ignorant of the law due to distance or isolation. For example, in a case in

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

, four hunters were

acquitted In common law jurisdictions, an acquittal certifies that the accused is free from the charge of an offense, as far as criminal law is concerned. The finality of an acquittal is dependent on the jurisdiction. In some countries, such as the ...

of game offenses where the law was changed during the period they were in the wilderness hunting. Another case, in early

English law English law is the common law legal system of England and Wales, comprising mainly criminal law and civil law, each branch having its own courts and procedures. Principal elements of English law Although the common law has, historically, be ...

, involved a seaman on a

clipper A clipper was a type of mid-19th-century merchant sailing vessel, designed for speed. Clippers were generally narrow for their length, small by later 19th century standards, could carry limited bulk freight, and had a large total sail area. "C ...

before the

invention of radio The invention of radio communication was preceded by many decades of establishing theoretical underpinnings, discovery and experimental investigation of radio waves, and engineering and technical developments related to their transmission and d ...

who had shot another. Although he was found guilty, he was pardoned, as the law had been changed while he was at sea. Although ignorance of the law, like other mistakes of law, is not a defence, a

mistake of fact A mistake of fact may sometimes mean that, while a person has committed the physical element of an offence, because they were labouring under a mistake of fact, they never formed the mental element. This is unlike a mistake of law, which is not ...

may well be, depending on the circumstances: that is, the false but sincerely held belief in a factual state of affairs which, had it been the case, would have made the conduct innocent in law.

In literature

The doctrine, "Ignorance of the law is no excuse," first shows up in the Bible in Leviticus 5:17: "If a person sins and does what is forbidden in any of the LORD's commands, even though he does not know it, he is guilty and will be held responsible." An alternate explanation of the origin of the maxim, though not particularly relevant to the modern context, can be found in the philosophy of the Greeks and Romans. Such were cultures heavily influenced by customary legal systems. Within such a system, law is learned as a person participates in the culture and customs of the community. Thus it is unreasonable to believe a person could have avoided learning them. These rules and customs were also interwoven with ethical and religious dialogue so that laws expressed what is right and that which is not. We find that

Cicero Marcus Tullius Cicero ( ; ; 3 January 106 BC – 7 December 43 BC) was a Roman statesman, lawyer, scholar, philosopher, and academic skeptic, who tried to uphold optimate principles during the political crises that led to the estab ...

wrote the following in ''

De re publica ''De re publica'' (''On the Commonwealth''; see below) is a dialogue on Roman politics by Cicero, written in six books between 54 and 51 BC. The work does not survive in a complete state, and large parts are missing. The surviving sections derive ...

'' (On the Republic):

There is a true law, right reason, agreeable to nature, known to all men, constant and eternal, which calls to duty by its precepts, deters from evil by its prohibition. This law cannot be departed from without guilt. Nor is there one law at Rome and another at Athens, one thing now and another afterward; but the same law, unchanging and eternal, binds all races of man and all times.

Minos In Greek mythology, Minos (; grc-gre, Μίνως, ) was a King of Crete, son of Zeus and Europa. Every nine years, he made King Aegeus pick seven young boys and seven young girls to be sent to Daedalus's creation, the labyrinth, to be eaten ...

(attributed to

Plato Plato ( ; grc-gre, Πλάτων ; 428/427 or 424/423 – 348/347 BC) was a Greek philosopher born in Athens during the Classical period in Ancient Greece. He founded the Platonist school of thought and the Academy, the first institution ...

) states the following conversation between

Socrates Socrates (; ; –399 BC) was a Greek philosopher from Athens who is credited as the founder of Western philosophy and among the first moral philosophers of the ethical tradition of thought. An enigmatic figure, Socrates authored no te ...

and his companion: ;Socrates :Come then, do you consider just things to be unjust and unjust things just, or just things to be just and unjust things unjust? ;Companion :I consider just things to be just, and unjust things unjust. ;Socrates :And are they so considered among all men elsewhere as they are here? ;Companion :Yes. . . . ;Socrates :Are things that weigh more considered heavier here, and things that weigh less lighter, or the contrary? ;Companion :No, those that weigh more are considered heavier, and those that weigh less lighter. ;Socrates :And is it so in Carthage also, and in Lycaea? ;Companion :Yes. ;Socrates :Noble things, it would seem, are everywhere considered noble, and base things base; not base things noble or noble things base. ;Companion :That is so.

Translation

Presumed knowledge of the law is the principle in

jurisprudence Jurisprudence, or legal theory, is the theoretical study of the propriety of law. Scholars of jurisprudence seek to explain the nature of law in its most general form and they also seek to achieve a deeper understanding of legal reasoning a ...

that one is bound by a law even if one does not know of it. It has also been defined as the "prohibition of ignorance of the law". The concept comes from

, and is expressed in the brocard ''ignorantia legis non excusat''. The essential public character of a law requires that the law, once properly promulgated, must apply to anyone in the

where the law applies. Thus, no one can justify his conduct on the grounds that he was not aware of the law. Generally, a convention exists by which the laws are issued and rendered accessible by methods, authors and means that are simple and well known: the law is readable in certain places (some systems prescribe that a collection of the laws is copied in every local city council), is made by certain authorities (usually sovereign, government, parliament, and derivative bodies), and enters into effect in certain ways (many systems for instance prescribe a certain number of days - often 15 - after issue). This is commonly intended as a

constitutional A constitution is the aggregate of fundamental principles or established precedents that constitute the legal basis of a polity, organisation or other type of entity and commonly determine how that entity is to be governed. When these princip ...

regulation, and in fact many

constitution A constitution is the aggregate of fundamental principles or established precedents that constitute the legal basis of a polity, organisation or other type of Legal entity, entity and commonly determine how that entity is to be governed. When ...

s or

statute A statute is a formal written enactment of a legislative authority that governs the legal entities of a city, state, or country by way of consent. Typically, statutes command or prohibit something, or declare policy. Statutes are rules made by le ...

s exactly describe the correct procedures. However, some recent interpretations weaken this concept. Particularly in civil law, regard can be had to the difficulty of being informed of the existence of a law considering the lifestyle of the average citizen. On the penal side, the quality of the knowledge of the law can affect the evaluation of the animus nocendi or the

mens rea In criminal law, (; Law Latin for "guilty mind") is the mental element of a person's intention to commit a crime; or knowledge that one's action (or lack of action) would cause a crime to be committed. It is considered a necessary element ...

, in that certain subjective conditions can weaken personal responsibility. The theme was widely discussed, also for political reasons, at the time of

the Enlightenment The Age of Enlightenment or the Enlightenment; german: Aufklärung, "Enlightenment"; it, L'Illuminismo, "Enlightenment"; pl, Oświecenie, "Enlightenment"; pt, Iluminismo, "Enlightenment"; es, La Ilustración, "Enlightenment" was an intel ...

and in the 18th century, given the heavy proportion of illiterate citizens in European countries (who would have some difficulties being aware of all the laws in a country). It was then argued that both the presumed knowledge and the heavily increasing corpus of national legislation were working in favour of lawyers rather than citizens. In recent times, some authors have considered this concept as an extension of (or at least as analogous to) the other ancient concept (typical of

) that no one can be punished under a law that was issued after the action was committed (non-retroactivity of the law. See ex post facto). This interpretation is however disputed, given that the matter would hierarchically more properly refer to a constitutional doctrine rather than to a civil or penal one. Some modern criminal statutes contain language such as stipulating that the act must be done "knowingly and wittingly" or "with unlawful intent," or some similar language. However, this does not refer to ignorance of laws, but having criminal intent.

Statutory law

This principle is also stated in

s: *Brazil: **Article 3rd of the Law of Introduction to Brazilian Law Norms. **Article 21 of the Brazilian Penal Code. *Canada:

Criminal Code A criminal code (or penal code) is a document that compiles all, or a significant amount of a particular jurisdiction's criminal law. Typically a criminal code will contain offences that are recognised in the jurisdiction, penalties that might ...

, section 19 *Philippines: Republic Act No. 386 "Civil Code of the Philippines", Article 3

Exceptions

In some jurisdictions, there are exceptions to the general rule that ignorance of the law is not a valid defense. For example, under U.S. Federal criminal tax law, the element of ''willfulness'' required by the provisions of the

Internal Revenue Code The Internal Revenue Code (IRC), formally the Internal Revenue Code of 1986, is the domestic portion of federal statutory tax law in the United States, published in various volumes of the United States Statutes at Large, and separately as Title 26 ...

has been ruled by the courts to correspond to a "voluntary, intentional violation of a known legal duty" under which an "actual good faith belief based on a misunderstanding caused by the complexity of the tax law" is a valid legal defense. See ''

Cheek v. United States ''Cheek v. United States'', 498 U.S. 192 (1991), was a Supreme Court of the United States, United States Supreme Court case in which the Court reversed the conviction of John L. Cheek, a Tax protester (United States), tax protester, for willful f ...

''. In '' Lambert v. California'' (1957), the

Supreme Court of the United States The Supreme Court of the United States (SCOTUS) is the highest court in the federal judiciary of the United States. It has ultimate appellate jurisdiction over all U.S. federal court cases, and over state court cases that involve a point o ...

ruled that a person who is unaware of a ''

malum prohibitum ''Malum prohibitum'' (plural ''mala prohibita'', literal translation: "wrong

s or because S, or s, is the nineteenth Letter (alphabet), letter in the Latin alphabet, used in the English alphabet, modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is English alphab ...

prohibited") is a List of Latin phrases, Latin phrase used in law to refer to conduct that constitutes an unlawful act only by virtue of statute, as opp ...

'' law cannot be convicted of violating it if there was no probability he could have known the law existed. It was subsequently ruled in '' United States v. Freed'' (1971) that this exception does not apply when a reasonable person would expect their actions to be regulated, such as when possessing narcotics or dangerous weapons. In ''

Heien v. North Carolina ''Heien v. North Carolina'', 574 U.S. 54 (2014), was a decision by the United States Supreme Court, ruling that a police officer's reasonable mistake of law can provide the individualized suspicion required by the Fourth Amendment to the United ...

'' (2014), the Supreme Court held that even if a police officer incorrectly believes that a person has violated the law due to a mistaken understanding of the law, the officer's "

reasonable suspicion Reasonable suspicion is a legal standard of proof in United States law that is less than probable cause, the legal standard for arrests and warrants, but more than an "inchoate and unparticularized suspicion or 'hunch; it must be based on "specif ...

" that a law was being broken does not violate the Fourth Amendment.

References

Bibliography

* "''Ignorantia Legis Neminem Excusat'', ''Manitoba Law Journal'', Vol. 2, Issue 10 (October 1885), pp. 145–157 * Nuhiu, Agim; Ademi, Naser; Emruli, Safet, "''Ignorantia Legis Neminem Excusat'' in the Area of Equality and Non-Discrimination—The Case of Macedonia", ''Journal of Law, Policy and Globalization'', Vol. 43, pp. 62–66 * Van Warmelo, P., "''Ignorantia Iuris'', ''Tijdschrift voor Rechtsgeschiedenis''/''Legal History Review'', Vol. 22, Issue 1 (1954), pp. 1–32 * Volcker, Sven B., "''Ignorantia Legis non Excusat'' and the Demise of National Procedural Autonomy in the Application of the EU Competition Rules: Schenker", ''Common Market Law Review'', Vol. 51, Issue 5 (October 2014), pp. 1497–1520 {{English criminal law navbox Brocards (law) Common law rules Criminal law Ignorance Legal rules with Latin names Legal doctrines and principles Promulgation