Criminal law is a body of public law which aims to deter and punish actions or omissions which are harmful to society. In criminal law, the state designates certain acts or omissions which are considered to be harmful to the public good as criminal offences, and prescribe sanctions for individuals who commit those offences.
In England and Wales, people accused of having committed a criminal offence are considered to be innocent until proven guilty by a court.
The standard of proof in criminal cases is high, meaning that the prosecution need to prove ‘beyond all reasonable doubt‘ that the defendant committed the crime. If they cannot do so, the defendant remains innocent and is not subject to sanctions.
To be found guilty of committing a criminal offence, it is usually required that the prosecution prove two things: actus reus (that the defendant committed the guilty act or omission) and mens rea (that the defendant had a ‘guilty mind’, or criminal intent, when they carried out the act or omission). However, some crimes do not require mens rea to be present at the time the act or omission was carried out; these are referred to as strict liability offences.
The vast majority of criminal cases in England and Wales are prosecuted by the Crown Prosecution Service (CPS), although private prosecutions can be brought by private individuals or organisations.
Criminal court cases are cited in the style of R v Smith, where R refers to ‘Regina‘ (if the monarch at the time is Queen) or ‘Rex‘ (if the monarch at the time is King), and ‘Smith’ is the name of the defendant. When spoken, the case would be described as ‘the Crown against Smith’ or ‘the Crown and Smith’.