In jurisprudence, Animus nocendi (Latin animus, "mind" + gerund of noceo, "to harm") is the subjective state of mind of the author of a crime, with reference to the exact knowledge of illegal content of his behaviour, and of its possible consequences. Jurisprudence (from Latin: juris prudentia — by the activity of prudentes; advisors, experts), is the philosophy, science, study, and application of law. ... Latin is the language that was originally spoken in the region around Rome called Latium. ... In linguistics a gerund is a kind of verbal noun. ...

In most modern legal systems, the animus nocendi is required as an essential condition to give a penal condemnation.

The animus nocendi is usually demonstrated by the verified presence of these elements:

• knowledge of a law that prohibited the discussed action or conduct (unless there exists a systemic obligation, pending on every citizen, that considers that the law has to be known by every adult — in this case the knowledge is presumed a priori);
• knowledge of the most likely consequences of his action;
• precise intention of breaking the law or of causing the verified effects of the action.

When the author of the crime had no animus nocendi, it is usually considered that the crime still exists, but the author is innocent, unless a responsibility for guilt can be found in his conduct: the typical case of a car accident in which a wrong or even hazardous manoeuvre causes personal injuries to another car driver, is then managed as a crime for the presence of injuries, yet the author will be not prosecuted as the author of the injuries (he did not want to hurt the other driver, thus he had no animus nocendi), but simply as the author of a dangerous conduct that indirectly caused said effects, and would be held responsible at a guilt title. Law (a loanword from Old Norse lag), in politics and jurisprudence, is a set of rules or norms of conduct which mandate, proscribe or permit specified relationships among people and organizations, provide methods for ensuring the impartial treatment of such people, and provide punishments for those who do not follow... A priori is a Latin phrase meaning from the former or less literally before experience. In much of the modern Western tradition, the term a priori is considered to mean propositional knowledge that can be had without, or prior to, experience. ... Guilt is a concept used in various ways in various contexts. ...

The animus nocendi is often absent in people with mental diseases, and in front of such people, a psychiatric expertise is usually required to verify the eventual animus. Minors too are in many systems considered little capable of a correct knowledge about the meaning or the consequences of their actions, and this is the reason for the common reduction of the passive capability of punishment they usually can receive.

A particular case of animus nocendi is the voluntas necandi. See also mens rea. In jurisprudence, voluntas necandi (Latin voluntas, will + gerund of neco, to kill) is describes the animus nocendi of a person who willfully kills another human being. ... Mens rea is a criminal law concept which focuses on the mental state of the accused and requires proof of a positive state of mind such as intent, recklessness, or willful blindness. ...