Concept
The Unlawful-Act Form
Common-law involuntary manslaughter
The Unlawful-Act Form
Most of this chapter has followed the negligence route to involuntary manslaughter, where the inquiry turns on how large the risk was and whether the defendant perceived it. The common-law definition names a second route, and this section is a compact tour of it. At common law, involuntary manslaughter was an unintentional killing that occurred either because the defendant acted with criminal negligence or during an unlawful act that did not amount to a felony or did not fall within the felony-murder rule.1 The second route replaces the measurement of risk with an examination of the underlying act. The question becomes whether the defendant was committing an unlawful act when the death occurred and whether that act proximately caused it. A defendant can therefore be guilty here even though the conduct was neither reckless nor grossly negligent as to death.2
The reason for the route is the same instinct that lies behind the felony-murder rule: a person who is already breaking the law answers for deaths that follow from the wrongdoing. The wrongfulness of the underlying act stands in for the culpable mental state the negligence route would demand, which is why this form can reach a defendant who never perceived any danger of death. That borrowed culpability is also the route's weakness, because a minor violation can produce a homicide conviction far out of proportion to the defendant's actual attitude toward human life. Lord Coke's traditional doctrine, which attached homicide liability to deaths during underlying crimes whatever their nature, was heavily criticized for its harsh results, and one of its earliest limits confined it to deaths during a felony or during an act intended to inflict great bodily injury.3 The limits taught below continue that narrowing.
The category also sits where it does because of the way murder is carved out above it. Under traditional common law, a homicide during an unlawful act intended to cause great bodily injury was murder, so the unlawful acts left over for manslaughter were those not so intended.4 In People v. Holtschlag the Michigan Supreme Court traced an 1886 formulation along those lines: an unlawful act directly dangerous to life made even an unintended death murder, while an unlawful act that was dangerous but not directly so, from which death unexpectedly resulted, was manslaughter.5 The court added that involuntary manslaughter is the catch-all homicide: an unintentional killing that is neither murder, voluntary manslaughter, nor justified or excused.6 Two kinds of unlawful act fill that territory today, and they are taken in turn, beginning with misdemeanors.
Misdemeanor-Manslaughter Rule
A death proximately caused during a misdemeanor, or during another unlawful act that is not a felony, is involuntary manslaughter.7 Statutes written in the older style say the same thing compactly, defining the offense as a killing in the commission of an unlawful act not amounting to a felony.8 Some states keep the misdemeanor-manslaughter rule under which causing death by risking fatal harm is manslaughter when the underlying act establishes guilt of a misdemeanor.9 The rule asks little about the size of the risk. In State v. Black, a Missouri decision, an assailant who committed an unlawful assault and battery without malice was guilty of manslaughter when death resulted, although the death was not intended and the assault was not of a kind likely to prove fatal.10 The battery was wrongful in itself, and the law attached the death to that wrong without requiring the defendant to foresee it.
The same borrowed culpability that makes the rule easy to satisfy makes it dangerous, since without limits every death that followed any minor violation would become a homicide. Courts and legislatures therefore narrow it in two ways. The first is causation: California's vehicular manslaughter provision, for example, declines to punish a homicide in driving unless it is the proximate result of the unlawful act, or of a lawful act done in an unlawful manner.11 The second is the kind of misdemeanor. Kansas's involuntary manslaughter statute reaches a killing during a misdemeanor only when the misdemeanor was enacted for the protection of human life or safety,12 which ties the borrowed culpability to the very harm the legislature was trying to prevent.
The difference from Black is the causal link. In Black the battery itself inflicted the fatal harm, while here the offense merely accompanied the death. Students lose this issue when they treat a violation that coincides with the death as the cause of it, because the rule reaches only a killing that results from the unlawful act.13
Felonies Outside Felony Murder
When a death occurs during a felony that does not qualify for felony-murder treatment, the killing is still at least involuntary manslaughter, so long as the felony proximately caused the death.15 The category exists because of the way the felony-murder rule divides felonies. Felony murder lifts killings in qualifying felonies up to murder, and the older formulation that confined unlawful-act manslaughter to acts that were not felonies was stated in recognition of that doctrine.16 A felony that fails the felony-murder test therefore falls into a gap. Nothing raises the killing to murder, yet nothing excuses it, and involuntary manslaughter is the catch-all for every unintentional killing that is neither murder, voluntary manslaughter, nor justified or excused.17 The words at least matter, because a defendant whose conduct also shows malice by another route, such as reckless indifference to an unjustifiably high risk to life, can still be charged with murder. The felony sets a floor and does not cap the grade.
Kansas draws the line within a single code. Its first-degree murder statute covers a killing in the commission of an inherently dangerous felony, a list that includes robbery and arson, while its involuntary manslaughter statute reaches a killing during a felony other than an inherently dangerous one when the felony was enacted for the protection of human life or safety.18 A death during a robbery is therefore murder, and a death during one of the remaining safety-oriented felonies is manslaughter. What makes a felony qualify for felony murder belongs to that doctrine and is not repeated here. For this section, only the consequence of failing the test matters.
The limit that governs misdemeanors governs felonies as well. The felony supplies culpability only for deaths it brings about.
The two routes are independent ways of reaching the same offense, so one death can satisfy either of them or both. A defendant whose misdemeanor also involved a gross deviation from reasonable care is liable under both, and the negligence route is then the sturdier ground because it does not depend on the jurisdiction keeping an unlawful-act rule. A defendant whose unlawful act was technical and who perceived no danger can be reached only through the unlawful-act route. Both routes sit beneath murder, so the malice question still comes first, and the Adams problem later in this chapter runs a single death down each route in turn.
Misdemeanor-Manslaughter Rule
The negligence route to involuntary manslaughter measures the size of the risk the defendant created. The unlawful-act route asks a different question: was the defendant committing an offense when the death occurred, and did that offense bring the death about? At common law, a death proximately caused during a misdemeanor or another unlawful act short of a felony was involuntary manslaughter, and the doctrine came to be called the misdemeanor-manslaughter rule.20 It works as a counterpart to the felony-murder rule, because an unintended killing that happens during wrongdoing is treated as a homicide. The theory is that the unlawful act stands in for the criminal negligence the prosecution would otherwise have to prove, much as breaking a safety statute can establish negligence per se in tort. The prosecution therefore proves the unlawful act, the death, and the causal link between them, and it need not show that the defendant was reckless or grossly negligent about the death itself.
The predicate offense can be modest. Battery is the most frequent one, and the liability it produces can exceed anything the defendant foresaw: a light tap meant only to stun, delivered to a victim who is a hemophiliac unknown to the defendant and who bleeds to death, makes the defendant guilty of manslaughter because the tap is a simple battery and a death resulted.21 In State v. Black, a Missouri decision, an unlawful assault and battery committed without malice supported a manslaughter conviction although the death was not intended and the assault was not of a kind likely to prove fatal.22 Traffic violations are the other common source. In State v. Hupf a driver who failed to obey a stop sign, in violation of a traffic ordinance, and caused a pedestrian's death was convicted of involuntary manslaughter under this doctrine, although a statute has since superseded that decision.23 Some states also accept a violation of a local ordinance or regulation as the unlawful act, and a felony that fails the felony-murder test can serve as well.
The ease of proving the rule explains the objection to it. Because the unlawful act supplies the culpability, punishment follows the accident of outcome: a traffic violation that happens to coincide with an unexpected death is no more blameworthy than the many identical violations that end without harm, yet only that one is punished as manslaughter.24 A Michigan statute shows the scale, since a driver who exceeds the limit by one mile per hour in a construction zone and kills a worker may be held strictly liable for manslaughter and face up to fifteen years in prison.25 Courts have also generally not surrounded this rule with the safeguards that confine felony murder, so misdemeanors that are not dangerous in any true sense can serve as the predicate.26 The criticism has accordingly tracked the criticism of felony murder, and the limits that follow are the responses to it.27
The most widely used limit sorts offenses by their character. A misdemeanor malum in se is wrong in itself, as a battery is, while a misdemeanor malum prohibitum is wrong only because a law forbids it, as a licensing or registration violation is. Most courts require either that the misdemeanor be malum in se or, when it is malum prohibitum, that the death be a foreseeable or natural consequence of the unlawful conduct.28 The limit ties punishment back to a risk the defendant actually created. Conduct that is wrongful in itself justifies treating the resulting death as the defendant's responsibility, while a technical violation justifies it only when the death grew out of the danger the violation represents. A death from running a stop sign meets the second branch, because striking a pedestrian is a natural consequence of ignoring the sign.
In both scenes a death occurs while the defendant is committing an offense, so the answer turns on the relationship between the offense and the death. In the Adams scene the offense is wrong in itself, and the death follows directly from it, which meets the threshold. In the registration scene the offense is merely prohibited, so the rule demands a foreseeable or natural connection to the death, and none exists.29 Students lose this issue when they treat an offense that merely coincides with the death as its cause.
Other jurisdictions draw the line differently. Because the in se and prohibitum labels are vague, some courts ask instead whether the violated statute was designed to protect people from death or serious injury, as opposed to protecting property or serving other ends, and the better view asks whether the defendant's conduct was dangerous in the particular death-causing situation.30 Others reach only a misdemeanor committed in a way that is dangerous under the circumstances of the case.31 Every version keeps the causation requirement, since the unlawful act supplies culpability only for a death it proximately caused.32
Many states have gone further and abolished the doctrine outright, led by the Model Penal Code, which rejects any misdemeanor-manslaughter analogue.33 Abolition leaves involuntary manslaughter resting on criminal negligence or recklessness, and the defendant's unlawful conduct remains available as evidence that the negligence was criminal.34 The reasoning is that a death both unintended and produced with no awareness of the risk makes heavy punishment hard to defend. On an exam, the first question is whether the jurisdiction keeps the rule: a problem that applies the common law or a retained statute calls for it, while one that applies the Model Penal Code does not.
Felonies Outside Felony Murder
A death during a felony does not always lead to a murder charge, because the common-law felony-murder rule reaches only a limited set of dangerous felonies. Which felonies qualify belongs to that doctrine, so the question here is narrower: what happens to a killing that falls outside it? The killing is still at least involuntary manslaughter when the death was a foreseeable consequence of the felony.36 At common law, a felony that did not come within the felony-murder rule could support liability under the unlawful-act theory in place of murder.37 Larceny is a typical occupant of this category, since the common law does not treat it as dangerous enough to sustain a felony murder charge.38
The category exists because of the way felony murder divides felonies. Felony murder raises a killing to murder only when the underlying felony qualifies, so a death during a felony on the other side of the line cannot be murder by that route. If the law stopped there, the prosecution could reach the defendant only by proving recklessness or gross negligence about the death itself, and a person engaged in a serious crime would escape homicide liability whenever that proof fell short. The unlawful-act theory closes the gap by accepting a felony that fails the felony-murder standard as the predicate, and the felony then stands in for the culpability toward the death, just as an unlawful act does elsewhere in this form of manslaughter. The prosecution proves the felony, the death, and the link between them, and it need not show that the defendant perceived any danger.
That arrangement invites an obvious worry. If the felony supplies the culpability, the category could swell into strict liability for every death that happens to coincide with a felony. Foreseeability is the control that prevents this result. The death must be a foreseeable consequence of the felony, which ties liability to the danger the felony itself created and leaves out deaths the felony did not bring about.39 The inquiry asks what a reasonable observer would expect the felony to produce, so a defendant who never thought about the danger can still be liable. That is why this route can succeed where the negligence route, with its demand for a gross deviation from reasonable care, would fail.
Students lose this issue when they treat a death that happens during any felony as manslaughter automatically, because the foreseeability requirement is what links the felony to the death.40 Some codes add a second filter at the front of the analysis. Kansas, for instance, reaches a killing during a felony other than an inherently dangerous one only when that felony was enacted for the protection of human life or safety.41 Under any version, the category sets a floor on liability and does not cap it, so a defendant whose conduct also shows malice by another route, such as reckless indifference to an unjustifiably high risk to life, can still face a murder charge.