Murder is the intentional, premeditated killing of another human being. The premeditation requirement for murder was historically described in the law as “malice aforethought.”

Laws regarding murder vary from state to state, and some states have a separate criminal offense of capital murder, which usually involves the most egregious circumstances, such as killing a peace officer in the line of duty or lying in wait to ambush and kill the victim. Capital murder offenses carry a potential death penalty.

And some states use the distinction of first degree murder (done with premeditation and punishable by death or life in prison) and second degree murder (generally an intentional killing without premeditation—also known as manslaughter or voluntary manslaughter in some states).

The criminal offense of murder is generally located in a state’s statutes—often in the penal or criminal code.

In New Hampshire, murder is classified under RSA 630:1-a as either 'capital murder' or 'first-degree murder.' Capital murder is the most serious form of homicide and includes circumstances such as the intentional murder of a law enforcement officer, murder for hire, murder during a kidnapping, and certain drug-related killings. Capital murder can be punishable by the death penalty, although New Hampshire repealed its death penalty in 2019, and this repeal applies to offenses committed after January 1, 2019. First-degree murder involves premeditated killing with 'deliberate intent to take away the life of another human being.' It is punishable by life imprisonment without the possibility of parole. Second-degree murder, under RSA 630:1-b, is defined as causing the death of another recklessly with extreme indifference to the value of human life or knowingly or recklessly causing the death under circumstances manifesting an extreme indifference to the value of human life. Second-degree murder does not require premeditation and is punishable by a term of imprisonment, which may be for life. The distinction between first and second-degree murder is crucial in determining the severity of the punishment.