Manslaughter is the unlawful killing or homicide of a human being without the premeditation or malice (malice aforethought) required for the criminal offense of murder.

Many states have two types of manslaughter: (1) voluntary manslaughter—the defendant intended to kill the victim, but did so in self-defense, or in the heat of passion and without premeditation, or the defendant was insane and did not understand that the killing was wrong; and (2) involuntary manslaughter—the defendant negligently or recklessly caused the death of another person—such as when a person is intoxicated while operating a motor vehicle and causes an accident that results in the death of another person.

Some states do not have separate criminal offenses for voluntary and involuntary manslaughter—these states may have the offense of manslaughter and identify certain aggravating factors that may enhance the penalties upon a conviction for manslaughter.

Manslaughter is a felony offense and may be punished by a lengthy prison term. Manslaughter laws are generally located in a state's statutes—often in the penal or criminal code.

In Alabama, manslaughter is defined under Section 13A-6-3 of the Alabama Code. The state recognizes manslaughter as a Class B felony, which occurs when a person recklessly causes the death of another person or causes the death of another person under circumstances that would constitute murder, except that he or she acts under the influence of extreme emotional disturbance for which there is reasonable excuse. The distinction between voluntary and involuntary manslaughter is not explicitly codified in Alabama law. However, the circumstances of the offense, such as acting in the heat of passion or through reckless behavior, can influence the classification and penalties. Manslaughter in Alabama is punishable by a prison term of 2 to 20 years. Unlike some states, Alabama does not have a separate statute for vehicular homicide; deaths resulting from driving under the influence can be prosecuted under manslaughter statutes if the elements of the offense are met.