When the authorities are investigating someone they accuse of a serious crime, physical evidence like DNA, fingerprints and video recordings are essential pieces of evidence. But for many crimes, especially violent crimes like homicide and assault, what was going on in the perpetrator’s mind at the time matters too.
Mens rea and the ‘guilty mind’
Many crimes on the books at the federal and state level here in Missouri include an element of intent. Usually, the law does not want to send someone to prison for a mistake. Thus, prosecutors often must prove both that the defendant committed the crime and had the intent to do so. Legally, this is known as mens rea, or a guilty mind.
For example, Missouri’s 2nd-degree murder statute requires proof beyond a reasonable doubt that the defendant “knowingly” took the victim’s life, did so with the intent of causing “serious physical injury,” or while perpetrating (or trying to perpetuate) a felony. A death caused by someone else’s unintentional negligence is unlikely to lead to a 2nd-degree murder conviction.
Exceptions apply
Like with most things in the law, there are exceptions to the intent requirement. Certain crimes are called “strict liability” crimes because the defendant’s intentions don’t matter. Statutory rape is an example of a strict liability crime.
The mens rea requirement often means the difference between homicide and manslaughter charges. It’s one factor in complicated criminal law matters like this. If you have been charged with a violent crime and you did not mean for what happened to happen, that is something you should make clear to your defense attorney.
