Actus Reus.

 Actus reus is a Latin term that translates to "guilty act" and is a fundamental concept in criminal law. It refers to the physical or external element of a crime, representing the actions or conduct that constitute a criminal offense. In order to establish criminal liability, both actus reus and mens rea (the mental state or intent) must typically be proven.

Actus reus encompasses a wide range of actions, behaviors, or omissions that can be deemed unlawful or prohibited by law. These actions can include anything from physically committing a crime, such as theft or assault, to failing to act when there is a legal duty to do so, such as in cases of negligence or omission.

It's important to note that not all physical actions or conduct are considered criminal acts. The act or omission must be prohibited or prescribed as an offense under the applicable criminal law. Furthermore, some crimes may require specific elements of actus reus, such as causation (the defendant's actions caused the prohibited result) or attendant circumstances (certain conditions or facts that must be present for the act to be criminal).

To establish actus reus, the prosecution must demonstrate that the accused engaged in the prohibited conduct voluntarily and without lawful justification. The specific elements required to prove actus reus will vary depending on the particular offense and the jurisdiction in which the crime occurred.

In summary, actus reus refers to the physical or external element of a crime and represents the guilty act or conduct that is required to establish criminal liability. It is one of the essential components that must be proven by the prosecution in a criminal case.