Murder vs. Manslaughter

Killing another person is commonly referred to as murder. However, the precise term for the killing of one person by another is homicide. Murder is a form of criminal homicide that has a precise legal meaning. Murder is usually defined as the "unlawful killing of another with malice aforethought (or "an abandoned and malignant heart"). Malice aforethought refers to the perpetrator's intention of doing harm.

There are different legal variations of murder, known as degrees. Degrees of murder vary by the gravity (seriousness) of the offense (usually measured by the intent of the perpetrator) and the sentence assigned to that offense. For example, murder in the first degree, or first-degree murder, carries the sternest sentences and is usually reserved for murders committed with premeditation or extreme cruelty.

Manslaughter is also a form of criminal homicide. The difference between murder and manslaughter is in the element of intent. In order to commit voluntary manslaughter, a person must have committed a homicide, but have acted in the "heat of passion." This mental state must have been caused by legally sufficient provocation that would cause a reasonable person of ordinary temperament to lose self-control. To convict a person of manslaughter, it must be proved that the person who committed the homicide had adequate provocation (this cannot involve words alone), acted in the heat of passion, and lacked the opportunity to cool that passion. There must also be a connection between the incident of provocation, the heat of passion, and the act that caused the homicide.

Involuntary manslaughter is manslaughter resulting from a failure to perform a legal duty expressly required to safeguard human life, from the commission of an unlawful act not amounting to a felony , or from the commission of an act involving a risk of injury or death that is done in an unlawful, reckless, or grossly negligent manner. Involuntary manslaughter is a relatively new legal concept. Its exact definition varies greatly by jurisdiction, and is sometimes known as second- or third-degree manslaughter.

In order to convict someone of either murder or manslaughter, the distinct elements of each crime must be proved beyond a reasonable doubt, and the actions of the perpetrator cannot be explained or excused by any legal defense, excuse, or justification. Murder and manslaughter also differ in the sentences imposed for each crime. As the perpetrator of manslaughter is assumed to have evidenced less mental culpability, the sentence for manslaughter is usually less than that for murder.

see also Assassination; Criminal responsibility, historical concepts; Death, cause of; Death, mechanism of; Serial killers.