Unit 14: Introduction to Homicide


  • Dressler 473-479 (through 31.02)

  • Homicide Statutes (CP)

  • Keeler (CP)

Key Terms: 

  • homicide

  • human being

  • death

  • brain death

  • criminal homicide

  • murder

  • malice


Homicide is “the killing of a human being by another human being.” Not all homicides are criminal—note that the definition ascribes no blameworthiness to the act of killing.

The definition of homicide requires us to define the term “human being.” At common law, a fetus had to be born alive to be considered a human being. Although this definition still applies in the majority of jurisdictions, it is losing traction for its failure to account for scientific advances in fetal viability. Additionally, the definition is criticized for creating counter-intuitive situations in which a fetus that died immediately after birth would be a human being, but a fetus that died immediately before birth would not. In response, a growing number of states have modified the definition of “human being” to include a viable unborn fetus.

Criminal homicide also requires us to define “death.” Historically, death was defined as the permanent end of blood circulation and the various essential bodily functions that rely on blood circulation. This definition is now unsatisfactory, as modern medicine has made possible the artificial maintenance of heart and lung functions long past the point when a person is capable of sustaining these functions without life support. In recent decades, medical experts have begun to define death in terms of “brain death,” or a lack of brain function on cognitive, motor, and reflexive levels. A majority of jurisdictions have since incorporated “brain death” into their definition of death.

Homicide committed without justification or excuse is criminal homicide, of which there are many varieties.  (We will cover justification and excuse in more detail when we look at defenses later in the course.)

Murder is “the killing of a human being by another human being with malice aforethought.” Manslaughter is an unlawful killing without malice aforethought. “Aforethought” can be satisfied by any amount of thought preceding the killing – even just a second. “Malice” in a criminal law setting refers to 1) an intent to kill, 2) an intent to inflict serious bodily harm, or 3) a “depraved heart,” or an extreme disregard for the value of human life.  Intent is often inferred from knowledge of the probable consequences of an action. Additional factors (such as use of a deadly weapon) can also aid a finding of intent.  In some jurisdictions, the malice requirement can be met when a death occurs during the commission or attempted commission of a felony (sometimes called felony-murder).

Intentional manslaughter includes an intent to kill (which would usually satisfy the malice requirement for murder) that is mitigated because the killer acted in a “sudden heat of passion” as a result of “adequate provocation.”

Unintentional manslaughter is homicide committed without malice but which is neither justified nor excused because it is committed recklessly or criminally negligently.  Alternatively, in some jurisdictions, any unintentional killing that takes place during the commission of a misdemeanor is considered involuntary manslaughter, sometimes called “misdemeanor-manslaughter.”

Specific grading of murder and manslaughter (e.g., first-degree, second-degree) varies from jurisdiction to jurisdiction.

Questions for Review:

Q1. Suppose Dr. Brown is caring for John, who is in a coma following a tragic accident.  Dr. Brown provides life support necessary to keep John’s internal organs functioning. Eventually, John’s family comes to Dr. Brown and tells her that it was John’s wish that, should he be in this situation, he be removed from life support. Dr. Brown complies, and John’s body quickly ceases to function. Has Dr. Brown committed homicide? Why or why not? For now, disregard questions of causation (i.e. whether or not Dr. Brown’s conduct is actually responsible for the cessation of bodily functions).

Q2. Suppose the same facts as above, except John’s body can function on its own. However, because he cannot eat, he requires life support in order to provide nutrients to keep his body functioning. Once again, Dr. Brown removes life support, and John’s bodily functions eventually cease. Was Dr. Brown’s conduct here homicide? How is this different from the above hypothetical, if at all? For now, disregard questions of causation (i.e. whether or not Dr. Brown’s conduct is actually responsible for the cessation of bodily functions).

Q3. What differentiates intentional manslaughter from murder? Why do you think criminal codes make this distinction?

Q4. What do you think is the difference between justified homicide and excused homicide? Why might this distinction matter?