Module 2: Homicide

Criminal homicide is the unlawful killing of another human being. From there, the law grades it by how culpable the killing was: murder (killing with malice aforethought), voluntary manslaughter (what would be murder, reduced by adequate provocation), and involuntary manslaughter (an unintentional killing from criminal negligence). The rest of this module is really about sorting any given killing into the right one of these categories.

This graded structure isn’t how homicide law always worked — worth knowing where it came from. At early common law, murder was a single, undifferentiated capital offense with no degrees at all. Pennsylvania created the first modern degree system in 1794, specifically to limit the death penalty to the most culpable killings (premeditated ones, and a short list of felonies) rather than every intentional killing alike. Most American jurisdictions followed that model, which is why “degrees” of murder are a legislative refinement layered on top of the older common-law malice framework, not something malice itself ever required.

Example. Three different endings to the same start — Peter and John argue. If Peter calmly decides to kill John and does, that’s murder. If Peter kills John in a sudden rage after John commits a serious battery against him, that may be voluntary manslaughter. If Peter, while recklessly swinging a heavy object during the argument with no intent to hit anyone, accidentally kills John, that may be involuntary manslaughter. Same rough setup, three very different results, because homicide law cares enormously about mental state and circumstance, not just outcome.

Murder requires malice aforethought, which is satisfied by any of four traditional forms: intent to kill, intent to cause serious bodily harm, depraved heart (extremely reckless conduct showing a conscious disregard for human life), or felony murder (a death during an inherently dangerous felony). Malice, despite the name, doesn’t require hatred or even wanting anyone dead — depraved heart murder is the clearest example of that.

Commonwealth v. Malone is the classic depraved heart case, and it’s worth knowing precisely because no one wanted anyone to die. Two teenagers played a game of “Russian roulette,” each putting a single bullet in a revolver, spinning the cylinder, and pointing it at the other, believing (based on how the earlier round went) the odds of firing on a live chamber were low. The gun fired on Malone’s turn, killing his friend. The court upheld a murder conviction: Malone didn’t need to want his friend dead, or even think death was likely — consciously engaging in conduct with an obvious, extreme risk to life, indifferent to the outcome, is malice all by itself.

Example. Peter shoots John dead on purpose — intent to kill. Peter beats John intending only serious injury, and John dies anyway — intent to cause serious bodily harm, still malice. Peter fires a gun randomly into a crowded subway car, wanting to hit no one in particular but consciously disregarding the extreme risk, and a bullet kills John — depraved heart, malice again, despite Peter never wanting anyone dead at all.

Many jurisdictions split murder into degrees. First-degree murder classically requires premeditation (thought about beforehand) and deliberation (a cool, calm decision, not an impulsive one) — or, in many statutes, occurs automatically when the killing happens during certain enumerated dangerous felonies. Everything else generally falls to second-degree murder.

Courts genuinely disagree about how much time premeditation actually requires, and two cases mark the real split. Commonwealth v. Carroll took a permissive view: a husband, after an argument, shot his sleeping wife with a gun that happened to be within reach — the court found premeditation and deliberation could form in mere seconds, holding that no minimum length of time is required, only that the decision was actually made beforehand. State v. Guthrie pushed back decades later, worried that an “any amount of time” standard erases the real distinction between first and second degree: it required genuine evidence of actual reflection, not just an instant of intent immediately before an impulsive act.

Example. Peter spends several calm hours planning exactly how and when to kill John, then carries it out precisely as planned — premeditation and deliberation, first-degree murder. Compare that to Peter, in a sudden, unplanned burst of extreme recklessness, doing something that kills John with no advance thought at all — that depraved-heart killing is murder, but without premeditation and deliberation, it typically lands at second degree instead.

Felony murder lets the intent to commit an inherently dangerous felony substitute for the malice murder would otherwise require — no separate proof of intent to kill is needed. Real limits apply, though: under the merger doctrine, a felony that’s an integral part of the killing itself (like assault) can’t serve as the predicate felony, or felony murder would swallow ordinary homicide law. And under the majority agency approach, liability is generally limited to killings committed by a felon or their agent — not a resisting victim’s own lawful act, though some jurisdictions instead follow a broader proximate cause approach.

People v. Stamp shows felony murder’s causation reach going further than ordinary foreseeability might suggest. During an armed robbery, the terrified store owner — who, unknown to the robbers, had a preexisting heart condition — suffered a fatal heart attack shortly after the robbers fled, with no physical contact involved at all. The court upheld felony murder liability anyway: felony murder doesn’t require the death to be a foreseeable result in the ordinary proximate-cause sense, only that it occurred during the felony — a felon takes the victim as he finds them, eggshell-skull-style, for purposes of this doctrine.

Example. Peter and Sam rob a store at gunpoint; unplanned, a struggle breaks out and a bystander dies. Peter can be convicted of felony murder without any separate proof he personally intended the death — the armed robbery itself supplies the malice. Now suppose instead the store owner shoots and kills Sam, Peter’s co-felon, in self-defense. Under the agency approach, Peter likely isn’t liable for Sam’s death, since it was the store owner’s own lawful act, not a felon’s — though a proximate cause jurisdiction might reach the opposite result.

Voluntary manslaughter is what would otherwise be murder, reduced because the defendant killed in genuine heat of passion upon adequate provocation. Four pieces have to line up: the provocation must be objectively adequate (would provoke a reasonable person, not just this defendant), the defendant must have actually been in the heat of passion, no reasonable cooling-off period can have passed, and the provocation must have actually caused the killing.

Girouard v. State shows how firmly courts hold the “adequate” line at the objective standard. A husband, during a fight, was taunted by his wife with a series of cruel, deeply personal insults about his manhood and worth — genuinely wounding words, by any measure — and killed her shortly after. Maryland’s highest court held words alone, however cruel, are not legally adequate provocation, reaffirming the traditional, narrow categories (like discovered infidelity in the act, or a serious battery) rather than opening the door to a purely subjective “whatever actually enraged this defendant” standard.

Example. Peter walks in on his spouse’s infidelity in the act and, immediately and without any cooling-off, kills the other person — a classic case for voluntary manslaughter, since discovering infidelity in the act is a traditionally recognized adequate provocation. Now change one fact: Peter learns of the same affair, goes home, and three days later, no longer visibly enraged, kills the person. The provocation was real, but a reasonable cooling-off period has long passed — the reduction almost certainly no longer applies.

Involuntary manslaughter covers unintentional killings resulting from criminal (gross) negligence — carelessness well beyond ordinary civil negligence, but short of murder’s malice. Some jurisdictions also recognize misdemeanor manslaughter (the misdemeanor analog to felony murder), though many limit it to deaths that are a foreseeable result of the specific danger the misdemeanor was meant to prevent.

Commonwealth v. Welansky shows gross negligence can come from a systemic failure, not just a single careless act. The owner of a Boston nightclub, too ill to be physically present the night of a catastrophic fire, had nonetheless let exit doors stay locked and overcrowding go unchecked, creating conditions that turned a small fire into a mass casualty event. The court upheld his manslaughter conviction despite his physical absence: gross negligence can be built into how an operation is deliberately run and knowingly left unsafe, not only a specific unsafe act performed in the moment.

Example. Peter, cleaning a loaded gun carelessly in a way any reasonable person would recognize as dangerous, has it discharge and kill John — no intent to harm anyone, but a gross deviation from how a reasonable person handles a firearm. That’s involuntary manslaughter: unintentional, but culpable enough to be criminal rather than just a tragic accident with no criminal consequence at all.

Homicide is a result crime — the defendant’s conduct has to actually cause the death, tested in two steps. Factual (but-for) cause asks whether the death would have occurred, when and how it did, without the defendant’s conduct. Proximate (legal) cause then asks whether the death was a reasonably foreseeable consequence — an unusually unforeseeable intervening event, or a third party’s gross negligence or intentional wrongdoing, can be a superseding cause that breaks the chain, even where factual cause is clear.

People v. Kibbe shows just how far “foreseeable” actually reaches. Two men robbed an intoxicated victim and abandoned him, partially undressed, on the shoulder of a rural highway on a freezing night — he was struck and killed by a passing truck minutes later. The defendants argued the truck driver’s own act was the real, superseding cause of death. New York’s highest court disagreed: leaving a helpless, visibly impaired person exposed on a dark highway made exactly this kind of accident a genuinely foreseeable result of their own conduct — an intervening event doesn’t supersede liability just because it’s a different act by a different person, if it was itself a predictable consequence of what the defendant set in motion.

Example. Peter stabs John, who is rushed to the hospital and dies from an ordinary, foreseeable complication of treating that kind of wound — Peter remains the proximate cause; that risk was already baked into stabbing someone. Now suppose instead a doctor, completely independent of Peter, administers a clearly wrong medication in a way far outside normal medical error, and that’s what actually kills John. That kind of gross negligence by a third party can be a superseding cause — Peter may still answer for the stabbing itself, but not necessarily for the resulting death.