Involuntary Manslaughter Penalties and Sentencing

The law views involuntary manslaughter as an unintentional killing of a human being. Of course, every crime requires a culpable mental state. It may be more accurate to state that involuntary manslaughter reflects a lower level of culpability. As a result, federal and state laws in this area refer to causing the death of another person through criminal negligence or recklessness.

In contrast, first-degree murder involves the intentional killing of another person, often with premeditation. In second-degree murder, there is no malice aforethought but the killing is intentional. A felony murder starts with an offender committing a dangerous felony that then results in death. Voluntary manslaughter occurs when someone acts with the intent to cause death, but their conduct arises during the "heat of passion" brought on by provocation by the victim.

The law provides less punishment for involuntary manslaughter than for other forms of criminal homicide. In these cases, the offender may cause another person's death through reckless behavior. They may commit a minor offense without intent to kill. In sentencing, this distinction reflects a sense of fairness, making the punishment fit the crime.

Although involuntary manslaughter sentences differ among the states, the crime is most often treated as a felony. This means that it is punishable by at least 12 months in prison, along with fines and costs. Courts may also suspend prison or jail time and grant probation in appropriate cases.

Involuntary Manslaughter Penalties: Federal Law

Under federal law, involuntary manslaughter means an unlawful killing without malice. An offender might cause a death in the commission of an unlawful act that is not a felony. In other words, this could be a misdemeanor crime or violation. They might also cause death while engaged in a lawful but dangerous act without due caution or in an unlawful manner. 

Determinations of guilt or innocence may turn on causation and whether the offender's conduct was what a reasonable person would do under the same circumstances.

Federal law provides that someone convicted of involuntary manslaughter may face up to eight years in federal prison, but the base sentence for the crime under federal sentencing guidelines is a prison sentence of 10-16 months. It may increase with a finding that the underlying behavior was reckless conduct to 27-33 months. If the offender engaged in the reckless operation of a motor vehicle, the base sentence falls at 41-51 months. 

An offender's criminal record may also affect the sentence. In the end, judges retain a certain amount of discretion. They can depart from the guidelines.

Involuntary Manslaughter Penalties: State Law

While states often take their cues from federal law when drafting their own sentencing guidelines, they do vary on this issue. With involuntary manslaughter charges, states will generally give a range of possible sentences. Judges have broad discretion in determining what sentence to actually impose.

In making their determination, judges will also look to any aggravating and mitigating factors to decide the appropriate sentence. Aggravating factors are those that increase the severity of the crime and include things such as the defendant's history of reckless behavior or the use of a deadly weapon. Mitigating factors tend to decrease the sentence and can involve factors such as the defendant's acceptance of responsibility for the crime and lack of criminal history.

California law provides a good example. Like federal law, California provides that involuntary manslaughter is an unlawful killing without malice. Its definition of the crime mirrors the federal statute. In standard cases, California provides that conviction for charges of involuntary manslaughter may result in a prison sentence of two, four, or six years.

California also provides for the crime of vehicular manslaughter, which can apply when the offender causes death by the operation of a motor vehicle. California Penal Code Section 192 states an offender commits vehicular manslaughter when the killing resulted from:

  • Driving a vehicle in the commission of an unlawful act, not amounting to a felony, and with gross negligence; or driving a vehicle in a commission of a lawful act which might produce death, in an unlawful manner, and with gross negligence. (Section 192 (c)1)
  • Driving a vehicle in the commission of an unlawful act, not amounting to a felony, but without gross negligence; or driving a vehicle in a commission of a lawful act which might produce death, in an unlawful manner, but without gross negligence. (Section 192 (c) 2)
  • Driving a vehicle in connection with a vehicular collision or accident that was knowingly caused for financial gain (or for fraudulent purposes). (Section 192(c)3)

The potential sentence for someone convicted of vehicular manslaughter will vary based on which subsection is at issue. In cases where the offender engaged in gross negligence, the sentence may be up to one year in county jail or two, four, or six years in state prison. In cases where there was no gross negligence, the sentence may be up to one year in county jail. In cases where the accident stems from fraud, the sentence may be four, six, or 10 years.

Under California Penal Code Section 191.5, if the offender's vehicular manslaughter coincides with a DUI, then the penalties may increase. When gross negligence and the DUI are present, the sentence will be four, six, or 10 years. If the offender has a prior conviction, the sentence will be 15 years to life. 

If the vehicular manslaughter coincides with a DUI, but there is no gross negligence, then the offender may face up to one year in county jail or 16 months, two years, or four years in state prison. A judge or jury can determine gross negligence from the totality of circumstances, but special emphasis is given to illegal speeding displays and stunt shows in making the determination.

Examples of Involuntary Manslaughter Penalties and Sentencing

Fact patterns in cases of involuntary manslaughter are unique. They can involve the use of excessive force in a confrontation or a deadly error where the offender did not intend to cause death. Legal defenses include those common in other homicide offenses such as self-defense or accident. The following case examples highlight two well-known convictions for involuntary manslaughter and the penalties that followed.

In the early hours of New Year's Day in 2009, California law enforcement officer Johannes Mehserle shot and killed Oscar Grant III, an unarmed man on the San Francisco transit system. 

Officers had removed Grant from the train and placed him on the ground at the Fruitvale Station in Oakland while investigating a fight. Mehserle claimed he thought Grant was reaching for something in his waistband. Mehserle then pulled his pistol and shot Grant in the back. Mehserle claimed the shooting was a mistake as he intended to pull his taser.

The victim's death received intense media scrutiny as he was an unarmed young black man and Mehserle was a white police officer. The courts granted a change in trial venue due to the publicity. In 2010, a Los Angeles jury heard the case and convicted Mehserle of involuntary manslaughter, acquitting him of second-degree murder. The judge sentenced Mehserle to two years in prison. Many see Grant's death as a key event leading to the Black Lives Matter movement against police brutality.

On June 25, 2009, fans worldwide learned the sobering news about the death of Michael Jackson due to cardiac arrest from an overdose of sedative drugs. The popular singer and performer was preparing for a comeback tour to celebrate turning 50 the previous year. 

In preparing for the tour, Jackson suffered severe insomnia. He sought help from Conrad Murray, a cardiologist who had once treated Jackson's daughter. Jackson hired Murray as his personal physician. Murray began providing Jackson with the anesthetic drug propofol through an IV drip each night. The coroner ruled Jackson's death a homicide, citing an overdose of propofol, a drug normally used to sedate people in a hospital setting.

Police charged Murray with involuntary manslaughter after a lengthy investigation. In 2011, a jury convicted Murray, citing his reckless conduct in using propofol without monitoring equipment. Although propofol could be properly prescribed for a patient, the jury concluded Murray went beyond what was reasonable behavior with such a dangerous drug. The judge sentenced Murray to four years in prison, at that time the maximum sentence available.

Questions About Involuntary Manslaughter Penalties and Sentences? Ask an Attorney

While not as serious as murder charges, the penalties for involuntary manslaughter can still be harsh. The State alleges that a human life ended due to the offender's criminal negligence or reckless behavior.

In an involuntary manslaughter case, it's important to understand the laws that form the basis of the charge. Meeting with an experienced attorney can bring out the best defense strategy. Consider talking to a local criminal defense attorney as soon as possible.

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