Legal Latin
Commonly-used legal Latin phrases and maxims.
Actus reus
Actus reus is a Latin phrase which translates as ‘guilty act’. It refers to one of the two necessary components of a criminal offence, which the prosecution must prove beyond reasonable doubt that the defendant is responsible for carrying out. Most criminal offences require that the defendant committed the guilty act alongside mens rea (‘guilty …
Ex parte
Ex parte, or ex p for short, is a Latin term which translates as ‘outside of the party’. In English law, it refers to occasions where legal proceedings take place without one of the parties being present or represented. Before 2001, ex parte was used erroneously in case citations for judicial review applications, with the …
Ex post facto
Ex post facto is a Latin phrase which translates as ‘out of the aftermath’. It is usually used to refer to an ex post facto law, which is a law that has effect retroactively. An ex post facto law may criminalise or decriminalise a particular act, or it may make the penalty for a particular …
Ignorantia juris non excusat
Ignorantia juris non excusat is a Latin phrase which translates as ‘ignorance of the law is no excuse’. It means that no one can claim their ignorance of the law as a defence from having broken it. The principle is based on the fact that if ignorance was accepted as a valid defence, there would …
Mens rea
Mens rea is a Latin phrase which translates as ‘guilty mind’. It refers to one of the components of a criminal offence, which the prosecution must prove the defendant had while carrying out the actus reus (‘guilty act’). While the presence of mens reas must be proved to have existed in the majority of criminal …
Novus actus interveniens
Novus actus interveniens is a Latin phrase which translates as ‘new act intervenes’. It refers to an intervening act or omission which breaks the chain of causation, thereby relieving an individual of liability. Example Consider the following scenario: A is beaten up by B and ends up in hospital, in need of treatment. His injuries …
Obiter dicta
Obiter dicta (plural), or obiter dictum (singular), is a Latin phrase which translates as ‘by the way’ or ‘that which is said in passing’. It refers to statements made by a judge as part of their judgment which are not central to the final decision. They stand in contrast with the ratio decidendi which is …
Ratio decidendi
Ratio decidendi, or ratio for short, is a Latin phrase which translates as ‘the reason for the decision’. The ratio decidendi of a case is the legal argument or principle which forms the basis of the court’s overall judgment. It is what forms the binding precedent on which common law systems rely. The ratio of …
Res ipsa loquitur
Res ipsa loquitur is a Latin phrase which translates as ‘the thing speaks for itself’. It refers to the doctrine in tort law where negligence can be assumed to have taken place without direct evidence of the negligent act.
Stare decisis
Stare decisis is a Latin phrase which translates as ‘to stand by things decided’. It is a doctrine in common law systems which holds that previous court judgments should be binding on future courts, on the understanding that similar cases should be treated similarly. See precedent.