actus non facit reum nisi mens sit rea

This maxim states the general principle of criminal liability: a crime ordinarily requires both a guilty act (actus reus) and a guilty mind (mens rea), and the two must coincide. A person who causes harm accidentally, or without the required knowledge or intention, is not guilty of a serious offence.

In India the BNS rarely uses the word mens rea. Instead, each offence states its mental element (intentionally, knowingly, dishonestly, fraudulently, rashly), and the General Exceptions (mistake of fact, accident, insanity, infancy) work as defences. Some statutory offences are of strict liability, where the legislature has excluded mens rea expressly or by necessary implication.

Example

Since the accused honestly believed the bag was his own, actus non facit reum nisi mens sit rea applied and he was not guilty of theft, which requires dishonest intention.

In Indian law

• Chapter III, Bharatiya Nyaya Sanhita, 2023 (General Exceptions; old Chapter IV IPC)

See also

mens rea · actus reus · mistake of fact · general exceptions

Read more in the study notes

• Crime: meaning, elements and stages (Bharatiya Nyaya Sanhita)
• Liability: theory, conditions, the wrongful act, damnum sine injuria and causation (Jurisprudence)
• Mens rea: intention, motive, malice, negligence and recklessness (Jurisprudence)
• Duty, obligation and liability, and the sources from which they arise (Legal Concepts)
• Divisions of law: Salmond's classification, public and private, civil and criminal, substantive and procedural (Legal Methods)
• Methods of study: lectures, textbooks, the case method and technical terms (Legal Methods)