Voluntary vs. Involuntary Manslaughter: What Is the Difference?


Voluntary vs. Involuntary Manslaughter: What Is the Difference?When you think of homicide, murder is often what comes to mind. Homicide is when one person kills another person, after all. However, the often-misunderstood charge of manslaughter also falls under the umbrella of homicide. 

Manslaughter is split into two categories, voluntary and involuntary. But the voluntary vs. involuntary manslaughter distinction leaves many confused. 

What is the difference between voluntary and involuntary manslaughter? In short, the difference is whether the killing was on purpose. Voluntary manslaughter involves killing in the heat of passion, while involuntary manslaughter involves killing through criminal negligence. 

Understanding voluntary and involuntary manslaughter charges can be challenging. At the New Mexico Criminal Law Offices, we have helped many people understand and respond to manslaughter charges. We fight day in and day out for every one of our clients. If you have been charged with a crime, contact us today.

What Is Manslaughter?

When distinguishing voluntary vs. involuntary manslaughter, it helps to begin with the overlap. In New Mexico, manslaughter is “the unlawful killing of a human being without malice.” But what do “unlawful” and “malice” mean?

An “unlawful” killing is not excusable or justifiable. Excusable killing includes accidental deaths. Justifiable killing involves circumstances that justify your conduct, such as killing someone while defending yourself.

To kill someone with malice means that you intended to kill or gravely injure someone or did something you knew was likely to kill or gravely injure someone. 

Putting these definitions together, manslaughter occurs when someone unintentionally kills another person without a legal justification or excuse. With that understanding, we can explore each charge.

What Is Voluntary Manslaughter?

Voluntary manslaughter is “manslaughter committed upon a sudden quarrel or in the heat of passion.” The courts have elaborated on the less-than-obvious meaning of this phrase, referring to it as “legally sufficient provocation.” 

“Legally Sufficient Provocation”

To be legally sufficient, provocation must cause the person who killed another to feel extreme emotions that would prevent an ordinary person from exercising reason and self-control. The average person in the circumstance would not necessarily have killed the provoker, but they would have lost control of reason. 

In legal terms, provocation prevents you from forming the intent to kill, a requirement in most murder charges. For example, if you return home and discover your partner in the act of adultery, the distress may overwhelm you. If you kill your partner or the person they were with in a mental daze, you have not formed the intent to kill. In contrast, if you and your partner break up and they start dating someone new, you could not argue that the existence of the new relationship provoked you to kill.

Establishing Provocation

There are several limitations on how provocation can be applied. These limitations apply both to who you kill and general rules on what is enough to provoke.

First, it does not apply if you kill someone other than the person who provoked you. If you discover your partner cheating on you and kill a third party present in the house, provocation does not apply.

Additionally, words alone are seldom sufficient. No matter how offensive an insult is, it is not legally sufficient provocation.

The exception to this rule occurs when someone informs you about the occurrence of an event that would, if you witnessed it, be enough to provoke you. For example, if someone tells you they have been sexually abusing your child, you may lose control of yourself and kill them. However, if someone tells you they have slapped your child in the past, that would not be sufficient provocation. 

You also cannot have provoked the action that provoked you. One situation where this can happen is when you begin a physical fight with someone. If the person then responds in kind, you cannot say that they provoked you.

Finally, there must not be time for reason to return. If you have time to cool off, you are no longer in the heat of passion and have not been provoked. For example, if you discover your partner in the act of cheating on you, wait a few hours, then kill them or the person they were with, you had time to cool off. You could not argue the discovery of their adultery provoked you to kill.

The Punishment for Voluntary Manslaughter

A person who commits voluntary manslaughter is considered less culpable than one who commits murder. In New Mexico, voluntary manslaughter is a third-degree felony. The standard sentence given to a person convicted of voluntary manslaughter, absent aggravating or mitigating circumstances, is three years in prison.

What Is Involuntary Manslaughter?

Two types of killings may qualify as involuntary manslaughter: killing someone while committing a misdemeanor and killing someone through criminal negligence.

Killing While Committing a Misdemeanor

Misdemeanors are criminal activities deemed less serious than felonies by the legislature. If you kill someone while committing a misdemeanor, you may be charged with involuntary manslaughter. Such misdemeanors may include:

  • Assault,
  • Battery,
  • Stalking,
  • Trespass, and
  • Property damage.

Killing someone while excessively speeding or driving under the influence can lead to charges of involuntary manslaughter in many states. However, New Mexico has a homicide-by-vehicle statute that applies instead of involuntary manslaughter provisions. 

“Criminal Negligence”

Criminal negligence is conduct that is reckless, wanton, or willful—another phrase that requires explanation. You are criminally negligent if you ignore or disregard obvious risks of harm to the life or safety of others. If your criminal negligence kills someone, you can be charged with involuntary manslaughter.

You need not have anticipated killing someone. It is enough that your behavior showed sufficient disregard for the safety of others.

The Punishment for Involuntary Manslaughter

Considered a lesser offense than voluntary manslaughter, involuntary manslaughter is a fourth-degree felony. Absent aggravating or mitigating circumstances, fourth-degree felonies carry a sentence of 18 months in prison.

Voluntary vs. Involuntary Manslaughter

To review, voluntary manslaughter: 

  • Is one step below murder, 
  • Requires killing another person following legally adequate provocation, and
  • Is a third-degree felony carrying a standard sentence of three years.

Provocation must be great enough that an average person in the circumstance would have lost control of reason. 

In contrast, involuntary manslaughter: 

  • Is one step below voluntary manslaughter,
  • Requires either commission of a misdemeanor or criminal negligence, and 
  • Is a fourth-degree felony carrying a standard sentence of eighteen months.

You need not be aware that your conduct could kill someone to commit involuntary manslaughter.

Protect Yourself with Our Criminal Defense Attorneys

At the New Mexico Criminal Law Offices, we have over 20 years of experience defending people accused of criminal acts in New Mexico, including homicide in all forms. We know every client and every case is unique, and we always tailor our strategies to get you the best outcome we can. Reach out today for a consultation.