brainMens rea is a legal phrase used to describe the mental state a person must be in while committing a crime for it to be intentional. It can refer to a general intent to break the law or a specific, premeditated plan to commit a particular offense. To convict an accused person of a wrong doing, a criminal prosecutor must show beyond any reasonable doubt that the suspect actively and knowingly participated in a crime that harmed another person or their property.

The term mens rea comes from the writings of Edward Coke, an English jurist who wrote about common law practices. He advocated that “an act does not make a person guilty unless [their] mind is also guilty”. This means that while a person may have committed a criminal act, they can only be found guilty of criminal activity if the deed was deliberate.

To put it simply, mens rea determines whether someone committed a criminal deed purposefully or accidentally. This idea commonly applies to murder cases. The perpetrator’s mens rea, or mental state at the time of the killing, is an essential factor in whether they will be declared guilty or innocent. In order to receive a conviction, the lawyer must prove that the accused party had some intention or willingness to end the life of another person. On the other hand, if evidence shows the death to be accidental and unavoidable, the suspect must be declared innocent and set free.

In 1962, the American Law Institute created the Model Penal Code (MPC) to better define mens rea. It stated that in order to be blameworthy for any activity, the suspect must have done the act willingly, with the knowledge of what the final result would be or in a reckless manner with no consideration for the safety of others. Actions that meet these qualifications are viewed as intentional crimes, even if the perpetrator claims to be unaware that their activities were illegal. This concept falls under a U.S. law which states “ignorance of the law or a mistake of law is no defense to criminal prosecution”.

Every crime tried in court has two factors: the actus reus, the actual criminal act, and mens rea, the intent to commit that act. Prosecutors must prove that both of these conditions existed to win a conviction.


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