Murder is a form of homicide, that is, the illegal killing of another person. Traditionally, what sets aside murder from lesser forms of homicide, such as manslaughter, is “malice aforethought.” Under the common-law, malice aforethought was satisfied in each of four cases:
1. where the defendant intended to kill
2. where the defendant intended to cause serious bodily harm, and death resulted
3. where the defendant intended to commit a different felony, but during the course of which death resulted (the “felony-murder” rule); and
4. where the defendant did not intend to kill, but whose actions evinced “depraved indifference” to human life, from which they death resulted.
These don’t always apply today. For example, in some states, intent to cause serious bodily harm from which death results would be considered voluntary manslaughter. Other states have limited or eliminated the felony-murder rule.
Murder is typically divided into first and second degree, with first-degree murder featuring aggravating circumstances, such as premeditation or brutality in the crime.