Double homicide

Homicide refers to one human being killing another. Homicides can be divided into many overlapping legal categories, including murder, manslaughter, justifiable homicide, killing in war, euthanasia, and capital punishment, depending on the circumstances of the death. These different types of homicides are often treated very differently in human societies; some are considered crimes, while others are permitted or even ordered by the legal system.

Criminal homicide takes many forms including accidental or purposeful murder. The crime committed in a criminal homicide is determined by the mental state of the committing person and the extent of the crime. In many cases, homicide may be punished by life in prison or even capital punishment, but if the defendant in a capital case is sufficiently mentally disabled in the United States he or she cannot be executed. Instead, the individual is placed under the category of “insane”.

In some jurisdictions, a homicide that occurs during the commission of a crime may constitute murder, regardless of the actor's intent to commit homicide. In the United States, this is known as the felony murder rule. Much abbreviated and incomplete, the felony murder rule says that one committing a felony may be guilty of murder if someone, including the felony victim, a bystander or a co-felon, dies as a result of his acts, regardless his intent—or lack thereof—to kill.

Criminal homicides also include voluntary and involuntary manslaughter. An example of voluntary manslaughter is hitting someone with an intent to kill them, whereas involuntary manslaughter is unintentionally causing their death. The perpetrator does not receive the same legal action against them as a person convicted of murder.

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