Mala In Se
Mala in se (the singular is malum in se) is a term that signifies crime that is considered wrong in and of itself. The phrase is Latin and literally means wrong in itself. This class of crime is contrasted by crimes mala prohibita, the Latin term for "wrong because they are prohibited."
The distinguishing characteristic of crimes mala in se is not their severity, but that the citizenry feels they are morally wrong in and of themselves, and require no outside reasons to prove or justify their wrongness. For the most part, these are crimes that directly and visibly harm other people and their property, since it's traditionally these kinds of crimes that inspire the most fervent moral outrage.
Essentially all of the crimes identified in the old British common law system - the system which forms the foundation of criminal law in the United States - are identified as crimes mala in se. The punishment for these offenses was quite uniform: death. Of course, the opinions and practices of our society have changed over the centuries, and today's petty thieves no longer need fear the executioner's noose. While crimes mala in se remain, in general, the more heinous species of crime compared to crimes mala prohibita, they do not necessarily incur the heavier punishments (for example, a third drunk-driving conviction will warrant a much heavier punishment than a first-time conviction of petty larceny).
It is worth mentioning that this classification, "bad in itself," does not have very much official influence in modern criminal procedure. Technically, it matters very little in today's courts whether a crime is considered wrong in itself or whether it is wrong by statutory legislation. Instead, weight is placed on the defendant's history, the intention behind the defendant's actions, whether the crime was misdemeanor or felony and to what degree, and so on. "Mala in se" and "mala prohibita" are, it might be said, artifacts from the middle ages of Europe, which are preserved largely for their historical value.
Nevertheless, the moral feelings of the citizenry should not be overlooked while trying to understand the way that crime is classified and punished in the United States. While it would seem contrary for a society that prides itself as "a nation of laws" to agree that any crime is wrong in itself, rather than because it is against the law, there are not many people who would cite the law while explaining why rape is wrong.
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