Malum in Se

The Latin term malum in se translates roughly to “wrong in itself,” or “evil in itself.” In the law, the phrase is used to refer to someone’s actions that are inherently wrong, or sinful by nature, regardless of regulations of laws. This is different from malum prohibitum, which refers to an act that is only wrong because it is prohibited by law. To explore this concept, consider the following malum in se definition.

Definition of Malum in Se


maluhm in say


  1. An act that is wrong or evil by nature, regardless of statute or law.


Circa 15th century        New Latin

What is Malum in Se

Malum in se refers to certain acts that society judges as being inherently wrong, or even evil, whether or not laws have been enacted regarding them. Examples of malum in se acts include such things as rape, murder, child abuse, and theft. Such actions violate humanity’s natural, or moral principles.

By contrast, society has created laws and regulations to govern certain activities, and a violation of one of these is considered malum prohibitum, which is wrong because it is prohibited by law. For instance, a person driving 90 mph down a roadway on which the speed limit has been set at 40 mph has committed an act that is malum prohibitum. Most people wouldn’t consider this to be a morally reprehensible act, but it is still illegal.

Intent as a Factor in Malum in Se

The differentiation by the law in malum in se and malum prohibitum acts is whether or not intent is a required factor for prosecution. This may seem a bit confusing, but if someone is accused of committing a crime malum in se – which is something that is intrinsically bad or morally wrong, rather than prohibited by law – he or she must have had intent to do the illegal thing.

On the other hand, a person who commits a malum prohibitum act is strictly liable by simply violating the law, regardless of intent.

Entitlement to a Jury Trial

In the U.S., many crimes are considered to be “petty crimes,” which do not require a trial by jury, but can be heard by a judge at a bench trial. Each of these is a violation of some statute or ordinance. Because the question of whether a person committing a wrong malum in se requires a determination of whether he had intent, which is sometimes a difficult thing to determine, this type of case must be heard by a jury. Therefore, persons accused of having committed a crime malum in se, such as robbery, kidnapping, rape, and murder, are entitled to a jury trial.

Crime Malum Prohibitum Acts vs. Malum in Se Example

Bradley is late getting to work on a Saturday afternoon, and impatient when he arrives at the corner when the light is red. After looking both ways, Bradley crosses against the red light, jogging across the cross walk. A police officer down the block sees Bradley jaywalking, catches up to him, and issues him a citation.

When Bradley, some days later, discovers that this jaywalking ticket carries a hefty fine, he is outraged. He decides to go to court to address the cost that seems much too high for such a small violation. As it turns out, the city has seen a huge upturn in the number of pedestrian accidents – many of which are fatalities – and is cracking down on laws and ordinances that promote safety. Violation of a city ordinance regarding crosswalk safety is malum prohibitum – wrong only because it is prohibited by law. Bradley can take his case to the judge, rather than simply paying the fine, who will hear his arguments and decide Bradley’s case. This crime malum prohibitum is not entitled to a trial by jury.

In a different example of malum in se, Bradley’s unexpected crossing of the street against a red light causes Martha – a 70-year-old driver on her way to visit her grandchildren – to swerve and hit a light pole. Martha is severely injured, and later dies from her injuries. Bradley’s act in jaywalking is prohibited by law, and murder is malum in se. Should Bradley be charged with causing Martha’s death, he would be entitled to a jury trial, as the question of intent will need to be answered. He cannot be convicted of murder if he had no intent to kill Martha – or to engage in an activity that could reasonably be assumed would cause someone’s death.

Related Legal Terms and Issues

  • Bench Trial – A trial by a judge, without a jury.
  • Jury Trial – A trial before a group of people sworn to render a verdict based on the evidence presented.
  • Legislation – A law, or body of laws, enacted by a government.