Concept
Qualifying Unlawful Acts
Misdemeanor manslaughter
Qualifying Unlawful Acts
The basic rule depends on an unlawful act, and that phrase is looser than it first appears. Read literally, it could reach any conduct a court disapproves of, including civil wrongs, so the cases sort qualifying acts into categories instead of leaving the phrase open.1 Two categories carry nearly all of the doctrine. The first is the misdemeanor, which gives the rule its name, and the decided cases most often involve simple battery or a traffic offense such as speeding or drunk driving.2 The second is a felony that falls outside the felony-murder rule. Common law placed such felonies in the same category as misdemeanors, so a death caused by either kind of offense was unlawful-act involuntary manslaughter.3
Each category rests on its own reason, which is why the two are taught separately. A misdemeanor qualifies because the defendant committed it deliberately, and that deliberate lawbreaking stands in for the proof of carelessness about death that ordinary involuntary manslaughter would demand. The felony category exists to close a gap. The felony-murder rule reaches, at the least, certain dangerous felonies, so a felony outside that set produces no murder conviction even though the offender did something worse than a misdemeanant.4 Without a fallback, the law would hold a petty offender responsible for manslaughter after a death while releasing the perpetrator of a graver offense from homicide liability altogether. Placing the leftover felonies in manslaughter removes that anomaly by giving the unlawful-act theory a floor beneath murder.
Students who see a felony in the facts often assume that felony murder is the only homicide question, yet a felony that felony murder does not cover still leaves the manslaughter route open. The analysis therefore begins by classifying the predicate as a misdemeanor or as a felony outside the felony-murder rule. The next two sections take those categories in order, starting with misdemeanors and the question of how far that label stretches beyond ordinary state offenses.
Misdemeanors as Predicates
The first category of unlawful act is the misdemeanor, and the rule governing it is broad. In a jurisdiction that retains the doctrine, a death proximately caused during the commission of a misdemeanor is involuntary manslaughter, and nothing in that formulation asks which misdemeanor the defendant was committing.5 The breadth follows from the mechanism described earlier: the deliberate commission of an unlawful act stands in for proof of recklessness about death, so the identity of the offense does no work at the predicate stage. Any misdemeanor can therefore supply the culpability in principle, and the brakes that keep the rule from reaching trivial violations are separate limits taken up later in this chapter. In the decided cases, two kinds of misdemeanor appear far more often than the rest, simple battery and traffic offenses.6
Battery recurs because it is the commonest way for a person who deliberately breaks the law to bring about a death that nobody expected. The defendant hits the victim a light blow, meaning to inflict only minor harm, and the victim dies because of a weak heart, a thin skull, or a blood deficiency the defendant knew nothing about. It is almost universally held that this death is involuntary manslaughter.7 A criminal assault serves the same way: a defendant who closes on someone intending to strike but not to kill, and whose target suffers a fatal heart seizure from fright, is guilty even though a hand was never laid on the victim.8 The theory behind these results resembles the tort principle that a wrongdoer takes the victim as found, under which a person who intentionally injures another assumes the risk of even an unforeseeable death.9 How far that logic runs when the predicate is not an act of violence is a question for the later discussion of malum in se offenses and foreseeability.
Traffic offenses are the predicate that students most often miss, because a death on the road sounds like a negligence problem and sends the analysis looking for gross carelessness. Under the unlawful-act theory the search is shorter. In State v. Hupf, a driver failed to obey a stop sign in violation of a traffic ordinance and killed a pedestrian, and the driver was convicted of involuntary manslaughter, a result later superseded by statute in Delaware.10 The report did not turn on proof that the driver was grossly careless, because the violation itself carried the culpability. Speeding and drunk driving work the same way, and in State v. Davis an Iowa court affirmed a manslaughter conviction where a drunk driver caused a death.11 The trap lies in assuming that an ordinary traffic violation is too minor to count as a predicate.
The formal label on the offense matters less than students expect. Hupf involved a traffic ordinance rather than a state statute, and violations of local ordinances may qualify as unlawful acts to the same extent as violations of state criminal law, even where the jurisdiction classes them as civil wrongs instead of crimes.12 The rule keys on the defendant's deliberate breach of a legal command, and a municipal command binds the driver at the intersection as firmly as a state one does. Possession offenses can serve as well. In United States v. Walker, the defendant carried a pistol without a license, a misdemeanor, and dropped it in an apartment stairwell, where it fired and killed a bystander. The court treated the licensing offense as dangerous in itself, because an unlicensed carrier may lack the mental health, sobriety, or safety training that a license is meant to ensure.13 Walker also previews the filters taught later, since the District of Columbia formulation asks for a misdemeanor dangerous in itself, and Kansas confines the doctrine to misdemeanors enacted for the protection of human life or safety.14
The predicate must be a genuine violation attributable to the defendant. A defendant need not know that a law forbids the conduct, but on principle a fault-free violation should not help establish manslaughter, as where a statute makes it a misdemeanor to drive without working brakes and the brakes fail suddenly through no fault of the driver.15 Some courts go further, and in State v. Carman, Nebraska held that a public welfare offense requiring no mens rea, though enough for misdemeanor vehicle homicide, does not suffice for involuntary manslaughter.16 The route also closes when no law has been broken at all.
The predicate misdemeanor also carries accomplice liability with it. An accomplice is a person who intentionally aids, encourages, or procures another's offense, and the question here is whether such a person answers for a death that the principal's misdemeanor causes. The majority rule permits accomplice liability for crimes of recklessness or negligence so long as the secondary party has the mental state that the charged crime requires.17 Under the unlawful-act theory, the culpability the charged crime requires is the deliberate commission of the predicate misdemeanor, so a person who intentionally helps bring about a battery or a traffic offense has the very culpability the rule asks for. Some older decisions denied accomplice liability for unintended results altogether, reasoning that an accomplice must intend the result. The sounder approach, reflected in R. v. Creamer, recognizes that one can intentionally procure a dangerous wrongful act, and the court there stressed that the defendant must actually have procured the wrongful act itself.18
The breadth described here is only the starting point. The limits that courts place on it come later in this chapter, and the next section turns to the second category of predicate, the felony that falls outside the felony-murder rule.
Felonies Outside Felony Murder
The second category of predicate sits on the border between murder and manslaughter, and its rule has two parts. At common law, a felony that did not fall within the felony-murder rule could still support involuntary manslaughter under the unlawful-act theory if a death resulted, so the killing was manslaughter rather than murder.21 The modern formulation adds a condition on the death itself: a killing during such a felony is at least involuntary manslaughter, so long as the death was a foreseeable consequence of the felony.22 Because the category is defined by what felony murder leaves behind, the first task is to see how a felony can fail the felony-murder test.
Felony murder is one of the common-law routes to malice aforethought, the mental state that separates murder from manslaughter. Under it, the intent to commit the felony stands in for the intent to kill, the intent to inflict grievous bodily harm, or the extreme recklessness that murder otherwise demands.23 The substitution works only when the felony qualifies, and two limits on qualification matter here. The first is independence from the killing. Under the merger doctrine, crimes such as assault and battery cannot serve as the felony, because their elements are absorbed completely into the conduct that produces the death.24 In Shock, a Missouri court reached the same limit by reading the statutory reference to another felony as a collateral felony, one that could be completed even if no homicide occurred, rather than the acts of personal violence that make up the homicide itself.25 The second limit is inherent danger, because most states confine the rule to felonies that are inherently dangerous, such as rape, arson, robbery, and burglary.26 The usual trap is treating a felony battery committed on the victim as a felony-murder predicate.
Each limit rests on its own reason. Nearly every unintended killing begins with some unlawful violence against the victim, so if an aggravated battery that kills could itself serve as the felony, the intent to commit the battery would turn every such death into murder, and the line between murder and manslaughter would disappear. The inherent-danger limit works differently. The felon's intent can stand in for malice only because the felony carries a risk to life, and a felony without that risk gives no basis for the equivalence. The history points the same way: the common-law rule was absolute, which made sense when felonies were few and most involved violence or a risk of death, but expanding criminal codes created many low-risk felonies, and courts and legislatures answered with limits like these.27
When a felony fails either limit, the intent to commit it no longer supplies malice, so the killing cannot be murder on the felony-murder theory. The unlawful-act theory then takes over, because a felony that will not suffice for felony murder may still suffice for unlawful-act manslaughter.28 The foreseeability condition marks the outer edge of that fallback. The felony was committed deliberately, which supplies the culpability the manslaughter theory needs, but it supplies that culpability only for the risks the felony created, and a death with no connection to those risks is a coincidence. Requiring foreseeability keeps coincidence from becoming a conviction. Statutes can draw the same line in their text. Kansas treats a killing in the commission of an inherently dangerous felony as first-degree murder, and it makes a killing in the commission of any other felony involuntary manslaughter when that felony is one enacted for the protection of human life or safety.29 That protective-purpose requirement is one of the extra filters taken up later in this chapter.
The words at least in the formulation have a precise meaning. Manslaughter is the floor that remains once the murder theories are unavailable, and the same facts are never charged as murder and manslaughter at once. A felony that qualifies produces murder, and the fallback is never reached. The sorting therefore runs in a fixed order.
The third step matters because the fallback does not shelter a defendant who killed with malice by some other route. It catches only the killing that no murder theory reaches. It also coexists with ordinary involuntary manslaughter rather than replacing it. In a common exam pattern, a defendant who has committed a larceny, a felony that is not a felony-murder predicate, panics when the owner appears and throws a briefcase that kills. The felony-murder charge fails because larceny does not qualify, and the answer reduces to involuntary manslaughter, with negligence in the throw supplying the basis on those facts.30 The unlawful-act theory offers a second road to the same grade when the felony itself is the source of the culpability.
The two scenes show the two conditions working together. The first felony fails the felony-murder test because of the way it was committed, and the foreseeable death carries it into manslaughter. The second felony never reaches manslaughter because the death lies outside the risks the felony created.