The term criminal law , sometimes called penal law , refers to any of various bodies of rules in different jurisdictions whose common characteristic is the potential for unique and often severe impositions as punishment for failure to comply. Criminal punishment, depending on the offense and jurisdiction, may include execution, loss of liberty, government supervision (parole or probation), or fines. There are some archetypal crimes, like murder, but the acts that are forbidden are not wholly consistent between different criminal codes, and even within a particular code lines may be blurred as civil infractions may give rise also to criminal consequences. Criminal law typically is enforced by the government, unlike the civil law, which may be enforced by private parties.

The first civilizations generally did not distinguish between civil and criminal law. The first written codes of law were produced by the Sumerians. Around 2100-2050 BC Ur-Nammu, the Neo-Sumerian king of Ur, enacted the oldest written legal code whose text has been discovered: the 1 although an earlier code of Urukagina of Lagash is also known to have existed. Another important early code was the Code Hammurabi, which formed the core of Babylonian law. These early legal codes did not separate penal and civil laws.

The similarly significant Commentaries of Gaius on the Twelve Tables also conflated the civil and criminal aspects, treating theft or as a tort. Assault and violent robbery were analogized to trespass as to property. Breach of such laws created an obligation of law or discharged by payment of monetary compensation or damages.

The first signs of the modern distinction between crimes and civil matters emerged during the Norman Invasion of England.2 The special notion of criminal penalty, at least concerning Europe, arose in Spanish Late Scolasticism (see Alfonso de Castro), when the theological notion of God's penalty (poena aeterna) that was inflicted solely for a guilty mind, became transfused into canon law first and, finally, to secular criminal law.3 The development of the state dispensing justice in a court clearly emerged in the eighteenth century when European countries began maintaining police services. From this point, criminal law had formalized the mechanisms for enforcement, which allowed for its development as a discernible entity.

Criminal law is distinctive for the uniquely serious potential consequences or sanctions for failure to abide by its rules. Every crime is composed of criminal elements. Capital punishment may be imposed in some jurisdictions for the most serious crimes. Physical or corporal punishment may be imposed such as whipping or caning, although these punishments are prohibited in much of the world. Iniduals may be incarcerated in prison or jail in a variety of conditions depending on the jurisdiction. Confinement may be solitary. Length of incarceration may vary from a day to life. Government supervision may be imposed, including house arrest, and convicts may be required to conform to particularized guidelines as part of a parole or probation regimen. Fines also may be imposed, seizing money or property from a person convicted of a crime.

Five objectives are widely accepted for enforcement of the criminal law by punishments: retribution, deterrence, incapacitation, rehabilitation and restitution. Jurisdictions differ on the value to be placed on each.

• Retribution - Criminals ought to in some way. This is the most widely seen goal. Criminals have taken improper advantage, or inflicted unfair detriment, upon others and consequently, the criminal law will put criminals at some unpleasant disadvantage to "balance the scales." This belief has some connection with utilitarianism. People submit to the law to receive the right not to be murdered and if people contravene these laws, they surrender the rights granted to them by the law. Thus, one who murders may be murdered himself. A related theory includes the idea of "righting the balance."
• Deterrence - deterrence is aimed toward the specific offender. The aim is to impose a sufficient penalty to discourage the offender from criminal behavior. deterrence aims at society at large. By imposing a penalty on those who commit offenses, other iniduals are discouraged from committing those offenses.
• Incapacitation - Designed simply to keep criminals from society so that the public is protected from their misconduct. This is often achieved through prison sentences today. The death penalty or banishment have served the same purpose.
• Rehabilitation - Aims at transforming an offender into a valuable member of society. Its primary goal is to prevent further offense by convincing the offender that their conduct was wrong.
• Restitution - This is a victim-oriented theory of punishment. The goal is to repair, through state authority, any hurt inflicted on the victim by the offender. For example, one who embezzles will be required to repay the amount improperly acquired. Restitution is commonly combined with other main goals of criminal justice and is closely related to concepts in the civil law.

Public international law deals extensively and increasingly with criminal conduct, that is heinous and ghastly enough to affect entire societies and regions. The formative source of modern international criminal law was the Nuremberg trials following the Second World War in which the leaders of Nazism were prosecuted for their part in genocide and atrocities across Europe. In 1998 an International criminal court was established in the Hague under what is known as the Rome Statute. This is specifically to try heads and members of governments who have taken part in crimes against humanity. Not all countries have agreed to take part, including Yemen, Libya, Iraq, Israel and the United States.

In the United States, criminal prosecutions typically are initiated by complaint issued by a judge or by indictment issued by a grand jury. As to felonies in Federal court, the Fifth Amendment to the United States Constitution requires indictment. The Federal requirement does not apply to the states, which have a ersity of practices. Three states (Connecticut, Pennsylvania, and Washington) and the District of Columbia do not use grand jury indictments at all. The Sixth Amendment guarantees a criminal defendant the right to a speedy and public trial, in both state and Federal courts, by an impartial jury of the State and district wherein the crime was committed, and to be informed of the nature and cause of the accusation; to be confronted with the witnesses against him; to have compulsory process for obtaining witnesses in his favor, and to have the assistance of Counsel for his defense. The interests of the state are represented by a prosecuting attorney. The defendant may defend himself , and may act as his own attorney, if desired.

In most U.S. law schools, the basic course in criminal law is based upon the Model Penal Code and examination of Anglo-American common law. Crimes in the U.S. which are outlawed nearly universally, such as murder and rape are occasionally referred to as , while other crimes reflecting society's social attitudes and morality, such as drug prohibition and alcohol laws are referred to as .

Criminal law in England and Wales derives from a number of erse sources. The definitions of the different acts that constitute criminal offenses can be found in the common law (murder, manslaughter, conspiracy to defraud) as well as in thousands of independent and disparate statutes and more recently from supranational legal regimes such as the EU. As the law lacks the criminal codes that have been instituted in the United States and civil law jurisdictions, there is no unifying thread to how crimes are defined, although there have been calls from the Law Commission for the situation to be remedied. Criminal trials are administered hierarchically, from magistrates' courts, through the Crown Courts and up to the High Court. Appeals are then made to the Court of Appeal and then to the House of Lords on matters of law. Further appeals may be possible to the European Court of Justice or European Court of Human Rights.

Procedurally, offenses are classified as indictable and summary offenses; summary offenses may be tried before a magistrate without a jury, while indictable offenses are tried in a crown court before a jury. The distinction between the two is broadly between that of minor and serious offenses. At common law crimes are classified as either treason, felony or misdemeanor.

The way in which the criminal law is defined and understood in England and Wales is less exact than in the United States as there have been few official articulations on the subject. The body of criminal law is considerably more disorganised, thus finding any common thread to the law is very difficult. A consolidated English Criminal Code was drafted by the Law Commission in 1989 but, though codification has been debated since 1818, as of 2007, has not been implemented. Scotland and Northern Ireland have their own legal systems and are distinct jurisdictions within the United Kingdom of Great Britain and Northern Ireland.

Many laws are enforced by threat of criminal punishment, and their particulars may vary widely from place to place. The entire universe of criminal law is too vast to intelligently catalog. Nevertheless, the following are some of the more known aspects of the criminal law.

The criminal law generally prohibits undesirable . Thus, proof of a crime requires proof of some act. Scholars label this the requirement of an actus reus or . Some crimes – particularly modern regulatory offenses – require no more, and they are known as strict liability offenses. Nevertheless, because of the potentially severe consequences of criminal conviction, judges at common law also sought proof of an to do some bad thing, the mens rea or . As to crimes of which both and are requirements, judges have concluded that the elements must be present at precisely the same moment and it is not enough that they occurred sequentially at different times. 4

is Latin for "guilty act" and is the physical element of committing a crime. It may be accomplished by an action, by threat of action, or exceptionally, by an omission to act. For example, the act of striking might suffice, or a parent's failure to give food to a young child also may provide the actus reus for a crime.

Where the actus reus is a to act, there must be a . A duty can arise through contract,5 a voluntary undertaking,6 a blood relation with whom one lives,7 and occasionally through one's official position.8 Duty also can arise from one's own creation of a dangerous situation.9 Occasional sources of duties for bystanders to accidents in Europe and North America are good samaritan laws, which can criminalise failure to help someone in distress (e.g. a drowning child).10

An actus reus may be nullified by an absence of causation. For example, a crime involves harm to a person, the person's action must be the cause and of the harm.11 If more than one cause exists (e.g. harm comes at the hands of more than one culprit) the act must have "more than a slight or trifling link" to the harm.12

Causation is not broken simply because a victim is particularly vulnerable. This is known as the thin skull rule.13 However, it may be broken by an intervening act () of a third party, the victim's own conduct,14 or another unpredictable event. A mistake in medical treatment typically will not sever the chain, unless the mistakes are in themselves "so potent in causing death."15 \

is another Latin phrase, meaning "guilty mind." A guilty mind means an intention to commit some wrongful act. Intention under criminal law is separate from a person's motive. If Mr. Hood robs from rich Mr. Nottingham because his motive is to give the money to poor Mrs. Marion, his "good intentions" do not change his to commit robbery.16

A lower threshold of is satisfied when a defendant recognises an act is dangerous but decides to commit it anyway. This is recklessness. For instance, if tears a gas meter from a wall to get the money inside, and knows this will let flammable gas escape into a neighbour's house, he could be liable for poisoning.17 Courts often consider whether the actor did recognize the danger, or alternatively ought to have recognised a risk.18 Of course, a requirement only that one to have recognized a danger (though he did not) is tantamount to erasing as a requirement. In this way, the importance of mens rea has been reduced in some areas of the criminal law.

Wrongfulness of intent also may vary the seriousness of an offense. A killing committed with specific intent to kill or with conscious recognition that death or serious bodily harm will result, would be murder, whereas a killing effected by reckless acts lacking such a consciousness could be manslaughter.19 On the other hand, it matters not who is actually harmed through a defendant's actions. The doctrine of transferred malice means, for instance, that if a man intends to strike a person with his belt, but the belt bounces off and hits another, mens rea is transferred from the intended target to the person who actually was struck.20

Strict liability can be described as a "but for" cause of harm on part of the defendant. "But for" the action or product that caused the harm, nothing bad would have happened. Not all crimes require bad intent, and alternatively, the threshold of culpability required may be reduced. For example, it might be sufficient to show that a defendant acted negligently, rather than intentionally or recklessly. In offenses of absolute liability, other than the prohibited act, it may not be necessary to show anything at all, even if the defendant would not normally be perceived to be at fault. Most strict liability offenses are created by statute, and often they are the result of ambiguous drafting unless legislation explicitly names an offense as one of strict liability.

A , defined broadly, is an unlawful killing. Unlawful killing is probably the act most frequently targeted by the criminal law. In many jurisdictions, the crime of murder is ided into various gradations of severity, e.g., murder in the , based on . is a required element of murder. Manslaughter is a lesser variety of killing committed in the absence of , brought about by reasonable provocation, or diminished capacity. manslaughter, where it is recognized, is a killing that lacks all but the most attenuated guilty intent, recklessness.

Settled insanity is a possible defense.

Many criminal codes protect the physical integrity of the body. The crime of battery is traditionally understood as an unlawful touching, although this does not include everyday knocks and jolts to which people silently consent as the result of presence in a crowd. Creating a fear of imminent battery is an assault, and also may give rise to criminal liability. Non-consensual intercourse, or rape, is a particularly egregious form of battery.

Property often is protected by the criminal law. Trespassing is unlawful entry onto the real property of another. Many criminal codes provide penalties for conversion, embezzlement, theft, all of which involve deprivations of the value of the property. Robbery is a theft by force.Fraud in the UK is a breach of the Fraud Act 2006 by false representation, by failure to disclose information or by abuse of position.

Some criminal codes criminalize association with a criminal venture or involvement in criminality that does not actually come to fruition. Some examples are aiding, abetting, conspiracy, and attempt. However, in Scotland, the English concept of Aiding and Abetting is know as Art and Part Liability .

• Stanford Encyclopedia of Philosophy entry on Theories of Criminal Law
• Criminal Law Online
• Summaries of Recent U.S. Criminal Law Decisions

Criminal procedure refers to the legal process for adjudicating claims that someone has violated criminal law.

• The majority of civil law jurisdictions follow an inquisitorial system of adjudication, in which judges undertake an active investigation of the claims by examining the evidence and preparing reports.
• In common law systems, the trial judge, the investigators, and the prosecution are separate functions. After an investigation has been completed and charges lodged, the trial judge presides over proceedings grounded in the adversarial system of dispute resolution, where both the prosecution and the defense prepare arguments to be presented before the court. Some civil law systems have adopted adversarial procedures.

Proponents of either system tend to consider that their system defends best the rights of the innocent. There is a tendency in common law countries to believe that civil law / inquisitorial systems do not have the so-called "presumption of innocence", and do not provide the defense with adequate rights. Conversely, there is a tendency in countries with an inquisitorial system to believe that accusatorial proceedings unduly favor rich defendants who can afford large legal teams, and are very harsh on poorer defendants.

Currently, in many countries with a democratic system and the rule of law, criminal procedure puts the burden of proof on the prosecution – that is, it is up to the prosecution to prove that the defendant is guilty, as opposed to having the defense prove that s/he is innocent, and any doubt is resolved in favor of the defendant. This provision, known as the presumption of innocence, is required, for example, in the 46 countries that are members of the Council of Europe, under Article 6 of the European Convention on Human Rights, and it is included in other human rights documents. However, in practice it operates somewhat differently in different countries.

Similarly, all such jurisdictions allow the defendant the right to legal counsel and provide any defendant who cannot afford their own lawyer with a lawyer paid for at the public expense (which is in some countries called a "court-appointed lawyer"). Again, the efficiency of this system depends greatly on the jurisdictions. In some jurisdictions, the lawyers provided to indigent defendants are often overworked or less competent, or may not take much interest in the cases they have to defend.

Most countries make a rather clear distinction between civil and criminal procedures. For example, an English criminal court may force a defendant to pay a fine as punishment for his crime, and he may sometimes have to pay the legal costs of the prosecution. But the victim of the crime pursues his claim for compensation in a civil, not a criminal, action.1 In France, Italy, and many countries besides, the victim of a crime (known as the "injured party") may be awarded damages by a criminal court judge.

The standards of proof are higher in a criminal action than in a civil one since the loser risks not only financial penalties but also being sent to prison (or, in some countries, executed). In English law the prosecution must prove the guilt of a criminal “beyond reasonable doubt”; but the plaintiff in a civil action is required to prove his case “on the balance of probabilities”.1 Thus, in a criminal case a crime cannot be proven if the person or persons judging it doubt the guilt of the suspect and have a reason (not just a feeling or intuition) for this doubt. But in a civil case, the court will weigh all the evidence and decide what is most probable.

Criminal and civil procedure are different. Although some systems, including the English, allow a private citizen to bring a criminal prosecution against another citizen, criminal actions are nearly always started by the state. Civil actions, on the other hand, are usually started by iniduals.

In Anglo-American law, the party bringing a criminal action (that is, in most cases, the state) is called the prosecution , but the party bringing a civil action is the plaintiff . In both kinds of action the other party is known as the defendant . A criminal case against a person called Ms. Sanchez would be described as “The People vs. (=versus, or against) Sanchez” in the United States and “R. (Regina, that is, the Queen) vs. Sanchez” in England. But a civil action between Ms. Sanchez and a Mr. Smith would be “Sanchez vs. Smith” if it was started by Sanchez, and “Smith vs. Sanchez” if it was started by Mr. Smith.

Evidence from a criminal trial is not necessarily admissible as evidence in a civil action about the same matter. For example, the victim of a road accident does not directly benefit if the driver who injured him is found guilty of the crime of careless driving. He still has to prove his case in a civil action.1 In fact he may be able to prove his civil case even when the driver is found not guilty in the criminal trial.

Once the plaintiff has shown that the defendant is liable, the main argument in a civil court is about the amount of money, or damages , which the defendant should pay to the plaintiff. 1

• Criminal procedure in the United States
• Criminal law

• Israel, Jerold H.; Kamisar, Yale; LaFave, Wayne R. (2003). . St. Paul, MN: West Publishing. ISBN 0314146695.