What is involuntary manslaughter?

Involuntary manslaughter is defined as the unlawful killing of a human being without malice aforethought. In order to be involuntary manslaughter, the killing must have been unintentional. Different states have different definitions of or requirements for involuntary manslaughter. Generally, there are two ways to commit involuntary manslaughter: when a person causes the death of another during a lawful act carried out with a high level of negligence, or when a person causes the death of another while committing or attempting to commit a low-level unlawful act.

Involuntary Manslaughter Through Negligence

A person can commit a lawful act, but in doing so use a level of negligence that rises above typical civil negligence. If this negligence causes a death, that person can be charged with involuntary manslaughter. The type of language used to describe the level of negligence necessary to support a charge of involuntary manslaughter depends on the state. Many states use a variation of criminal negligence or gross negligence. These descriptors do not require the person who was negligent to have been aware of the level of the risk of his or her actions to be culpable for involuntary manslaughter. For example, if a person driving recklessly or under the influence of alcohol kills someone in an accident, this would be criminal negligence.

Other states use language such as wanton conduct or reckless conduct to describe the level of negligence necessary to trigger the possibility of involuntary manslaughter. If the state uses such terms, the test is more subjective than the test for criminal or gross negligence and requires the person to have known the risk of his or her action and yet taken it anyway.

In addition, a failure to act or to perform a duty can constitute involuntary manslaughter. In such situations, the person who caused the killing of another must have had some sort of duty toward the deceased. For example, if a parent fails to get adequate medical treatment for a child and the child dies as a result of that failure, the parent may be culpable for involuntary manslaughter.

Misdemeanor Manslaughter

The second type of involuntary manslaughter is commonly known as misdemeanor manslaughter. Generally, if a person is committing a misdemeanor and unintentionally causes the death of another, that person may be prosecuted for involuntary manslaughter. However, the kind of misdemeanor the person committed may, depending on the state, determine whether the person can be charged with involuntary manslaughter. In some states, the misdemeanor must be malum in se – illegal because it is wrong in itself – as opposed to malum prohibitum – illegal because it has been made so by statute. An example of a malum in se misdemeanor is assault, while an example of a malum prohibitum misdemeanor is driving without a license. The commission of a malum prohibitum misdemeanor can also lead to involuntary manslaughter charges if the death was a foreseeable consequence of the crime committed.

It is also possible to be culpable of involuntary manslaughter if a person causes a death while committing a non-dangerous felony. An example of a non-dangerous felony is practicing medicine without a license. States may differ in their definitions of dangerous and non-dangerous felonies. Causing a death during the commission of a dangerous felony may lead to a felony murder charge, which is much more serious than involuntary manslaughter.

Defenses to Involuntary Manslaughter Charges

Defenses to involuntary manslaughter charges depend on the type of charges. If the defendant is charged with involuntary manslaughter because of a negligent act that caused a death, one possible defense is to argue that the negligence did not rise to the level necessary to be gross or criminal. Arguing that the victim was also negligent, however, is not a defense in involuntary manslaughter charges.

If a defendant is charged with misdemeanor manslaughter, any defense to the underlying misdemeanor is also a defense to the involuntary manslaughter charge. This means that if the defendant assaulted someone with little force yet inadvertently caused the victim’s death, the defendant could argue that he was acting in self-defense. Because self-defense is a defense to assault, it is also a defense to the misdemeanor manslaughter charge.

Sentencing in Involuntary Manslaughter Cases

The sentence for a conviction of involuntary manslaughter depends on whether state or federal sentencing guidelines apply. If the conviction is in a federal court, the sentence can be anywhere from one to six years according to the judge's discretion. If the conviction is in a state court, that state’s guidelines apply, and those guidelines vary greatly depending on the state. Some states base the sentence on the level of severity. In those cases, the judge decides whether the situation calls for a low, middle, or high severity sentence and then the person is sentenced to the number of years corresponding to that level.

Other states designate the type of manslaughter as a class of felony, and then assign a sentence based on that class. New York State differentiates between negligent homicide and involuntary manslaughter due to recklessness. Negligent homicide belongs to a class that allows for a sentence of about five months to four years, and involuntary manslaughter due to recklessness belongs to a class that allows for a sentence of zero to fifteen years according to the discretion of the judge.

Consequences of a Conviction for Involuntary Manslaughter

Involuntary manslaughter will appear on a person’s criminal record. Some states also restrict people who have been convicted of involuntary manslaughter from owning or possessing guns, but usually only when the conviction is based on reckless use of a firearm. Involuntary manslaughter convictions may cause difficulty finding employment because it may appear on background checks, and in addition certain professional licenses will not be issued to those convicted of these types of crimes. In some states, landlords may have access to conviction records when running rental background checks as well. Manslaughter is a serious crime, and can have long lasting consequences, however, a criminal defense lawyer can often help by reducing the charges and decreasing the probability of a conviction.