Also known as:manslaughters · homicide · unlawful killing
Written by attorneys · grounded in primary & secondary sources — see below
A category of criminal homicide less culpable than murder that encompasses a killing committed recklessly or under the influence of extreme mental or emotional disturbance for which there is a reasonable explanation or excuse.
Sources & Authorities· 25 primary sources
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How it applies
Common Examples
6
Criminal Negligence Causes Death
Ming Ma left a loaded rifle unattended on a crowded shooting range after consuming several drinks. The weapon discharged when another patron bumped the table, killing Madison Meyers instantly. The state charged Ming with involuntary manslaughter on the theory that her grossly negligent handling of the firearm caused the death.
Victim Peacefulness Evidence Offered
Miles Montgomery was charged with manslaughter after stabbing Mina Mehta during a bar fight. The defense introduced testimony that Mina had initiated the physical confrontation. The prosecutor responded by calling character witnesses to testify that Mina had a reputation for peacefulness in the community.
Reckless Act Meets Homicide Definition
Mustafa Mahmoud drove his truck at excessive speed through a residential neighborhood while texting. He struck and killed Monica Morgan who was crossing the street. Under the applicable code, Mustafa's reckless conduct satisfied the elements of criminal homicide that constitutes manslaughter.
Juvenile Manslaughter Sentencing
A fifteen-year-old defendant was convicted of manslaughter after participating in an armed robbery that resulted in a victim's death. The court imposed a sentence of life imprisonment without parole. The sentence was reviewed for compliance with Eighth Amendment limits on juvenile sentencing for homicide offenses.
Criminal Negligence Standard Applied
Meridian Motors assigned an unlicensed mechanic to perform brake repairs on customer vehicles. One car later crashed because the brakes failed, killing the driver. The company was prosecuted for involuntary manslaughter because its deviation from reasonable care was substantially greater than ordinary civil negligence.
Dying Declaration in Manslaughter Case
Mosaic Retail's delivery driver was stabbed during a robbery and told responding officers that the attacker had initiated the attack without provocation. The victim died hours later. At the manslaughter trial the prosecution introduced the statement under the dying-declaration exception.
Common questions
Frequently Asked
5
What distinguishes voluntary manslaughter from involuntary manslaughter at common law?+
Voluntary manslaughter requires an intentional killing committed in the heat of passion upon adequate provocation before a reasonable cooling-off period. Involuntary manslaughter covers unintentional killings caused by criminal negligence or by the commission of an unlawful act that is not a felony qualifying for the felony-murder rule.
Supporting sources
Under the Model Penal Code, what mental states support a manslaughter conviction?
Manslaughter is established when a person recklessly causes death or when a homicide that would otherwise be murder is committed under the influence of extreme mental or emotional disturbance for which there is a reasonable explanation or excuse judged from the actor's situation.
Supporting sources
How does criminal negligence for involuntary manslaughter differ from ordinary civil negligence?+
Criminal negligence requires a substantially greater deviation from the conduct of a reasonable person than the deviation that would support civil liability. The defendant must have been aware of a substantial and unjustifiable risk that a reasonable person would have perceived.
Supporting sources
When may a prosecutor introduce evidence of a victim's peacefulness in a manslaughter prosecution?+
In any homicide case, including manslaughter, the prosecutor may offer evidence of the alleged victim's trait of peacefulness to rebut defense evidence that the victim was the first aggressor.
Supporting sources
Does the Eighth Amendment bar a life-without-parole sentence for a juvenile convicted of manslaughter?+
Yes. The Eighth Amendment categorically prohibits sentencing a juvenile offender to life imprisonment without the possibility of parole for any non-homicide offense, including manslaughter.
Supporting sources
homicide
victims in the United States are killed by their spouses. Mercy & Saltzman, Fatal Violence Among Spouses in the United States, 1976-85, 79 Am. J. Public Health 595 (1989). Thirty percent of…
Criminal Law & ProcedureHomicide · Intended killingsUBEFoundational