Legal Maxims
Principle of legality
no one can be convicted of, or punished for, a crime unless the law defined the crime and prescribed the punishment before the person engaged in the behavior that was defined as a crime.
Titius semper est errare acquitando quam in puniendo
It is always safer to err in acquitting than in punishing.
Blackstone's Ratio
It is better that ten guilty persons escape than that one innocent person suffer.
Melior est justitia vere praeveniens, quam severe puniens
Justice truly preventing is better that severely punishing.
ignorantia legis non excusat
Latin: ignorance of the law is not an excuse
Culpae poena par esto
Let the punishment equal the crime.
Dura lex sed lex
The law is hard, but it is the law.
actus non facit reum nisi mens sit rea
An act does not make a person guilty unless the mind is guilty.
Actus me invito factus non est meus actus
An act done by me against my will is not my act. (No person can be held liable for an involuntary act)
Mistake of Fact
Any mistaken belief other than a mistake of law. Examples include erroneous beliefs about the meaning of some term or about the identity of some person. In criminal law, a mistake of fact can usually operate as a defense so long as it is reasonable.
El que es cuesa de la causa es causa del mal causado
He who is the cause of the cause is the cause of the evil caused.
Ignorantia facti excusat
Ignorance of a fact excuses.
In dubio, pro reo
In doubt, for the accused
Cogitationis poenam nemo meretur
No man deserves punishment for a thought.
Nemo bis punitur pro una et eodem delicto
No one can be punished for one and the same offense.
mala prohibita
Offenses prohibited by law but not wrong in themselves; Do not require criminal intent.
Mala in se
Offenses that are wrong by their very nature; Requires criminal intent.
Presumption of innocence
The accused shall be presumed innocent until the contrary is proved beyond reasonable doubt.
Mens Rea
The required criminal state of mind that the accused should have at the time of the commission of the offense.
Nullum crimen sine lege, nulla poena sine lege
There is no crime without a law; there is no penalty without a law.
Actus Reus and Mens Rea
guilty act and guilty mind