Involuntary manslaughter is a criminal offense defined as the unintentional killing (homicide) of another person as a result of criminal negligence, recklessness, or during the commission of a misdemeanor (driving while intoxicated), infraction (speeding), or a felony crime that was not inherently dangerous. Involuntary manslaughter is usually a felony offense and often includes significant jail or prison time as potential punishment.

Involuntary manslaughter laws vary from state to state and are generally located in a state’s statutes—often in the penal or criminal code.

In Illinois, involuntary manslaughter is addressed under 720 ILCS 5/9-3 of the Illinois Compiled Statutes. It is defined as the unintentional killing of an individual without lawful justification by an act that is likely to cause death or great bodily harm to another, and which is committed recklessly. Recklessness, in this context, means that the person acts with a conscious disregard for the substantial and unjustifiable risk that the act may cause. Involuntary manslaughter in Illinois is considered a Class 3 felony, which can result in a prison sentence of 2 to 5 years, and fines up to $25,000. Additionally, if the victim is a family or household member and the act was committed in a 'reckless manner,' it may be charged as 'reckless homicide,' which carries similar penalties. It is important to note that the specific circumstances of the incident can influence the severity of the charges and penalties. An attorney can provide more detailed information based on the facts of a particular case.