Legal Definitions of Types of Murder and Manslaughter

Homicide is the killing of a human being or fetus.  Not all homicide is unlawful.  Someone who kills in lawful self-defense or defense of another has committed a homicide but has not committed a crime.  The same is true of a death that occurs by accident, provided that the accident was not caused by criminal negligence. 

An unlawful homicide is either murder or manslaughter.  A homicide becomes murder if the perpetrator committed the crime with “malice aforethought” or committed the homicide while committing one of a list of felonies.  All other unlawful homicides are manslaughter. 

The prosecution can prove “malice aforethought” either by showing that the defendant intended to kill, or that the defendant committed an act that was highly dangerous to human life, was aware of that danger, and committed the act anyway. 

Murder

Murder is divided into two categories: first degree murder and second degree murder.

First Degree Murder

First degree murder is a murder that is:

• Premeditated and deliberate, OR
• Committed by use of a destructive device, explosive, weapon of mass destruction, armor-penetrating ammunition, poison, torture, lying in wait, by discharging a firearm from a motor vehicle, OR
• Committed in the perpetration of robbery, burglary, arson, rape, carjacking, mayhem, kidnapping, train wrecking, or Penal Code sections 206, 286, 287, 288 or 289.

First degree murder is punished by a sentence of 25 years to life in state prison. 

Special Circumstance Murder 

If the prosecution can prove that a murder was committed under certain “special circumstances,” then the defendant may receive the death penalty or a sentence of life in prison without the possibility of parole. 

Penal Code section 190.2 contains a list of special circumstances.  They include:

• Intentional murder for carried out for financial gain.
• Murder with a prior conviction for first or second degree murder.
• Multiple murder convictions in the current proceeding.
• Murder perpetrated by a concealed destructive device, bomb, or explosive.
• Murder that is committed to prevent arrest or to attempt or complete an escape.
• Murder that is committed by mailing a bomb, explosive or destructive device
• Intentional killing of peace officer engaged in the lawful performance of his or her duties
• Intentional killing of a federal law enforcement officer engaged in the lawful performance of his or her duties.
• Intentional killing of a firefighter engaged in the lawful performance of his or her duties.
• Intentional killing of a witness to a crime.
• Intentional killing of a prosecutor carried out in retaliation for, or to prevent the performance of, the victim’s official duties.
• Intentional killing of a judge or former judge carried out in retaliation for, or to prevent the performance of, the victim’s official duties.
• Intentional killing of an elected or appointed federal, state or local government official carried out in retaliation for, or to prevent the performance of, the victim’s official duties.
• Murder that is especially heinous, atrocious, or cruel.
• Intentional murder committed by means of lying in wait.
• Intentional murder that is motivated by the victim’s race, color, religion, nationality, or country of origin.
• Murder committed in the course of a robbery, kidnapping, rape, sodomy, lewd or lascivious act on child under 14, oral copulation, burglary, arson, train wrecking, mayhem, rape by instrument, or carjacking.
• Intentional murder involving the infliction of torture.
• Intentional murder committed by the administration of poison.
• Intentional killing of a juror in retaliation for, or to prevent the performance of, the juror’s duties.
• Murder perpetrated by means of discharging a firearm from a motor vehicle at another person outside the vehicle with the intent to inflict death.
• Murder committed intentionally, while the defendant was an active participant in a criminal street gang, carried out with the intent to further the gang’s activities.

Second Degree Murder 

All murders that do not qualify as first degree murder are murders of the second degree. 

Second degree murder is punished by a sentence of 15 years to life in state prison. 

Attempted Murder 

In order to prove the crime of attempted murder, a prosecutor must prove that the defendant had the specific intent to commit murder, and committed a direct but ineffectual act toward its commission.  Attempted murder that is premeditated and deliberate results in a punishment of life in prison, with the possibility of parole. Attempted murder that is committed without premeditation and deliberation may result in a state prison sentence of 9 years. 

Manslaughter 

If the prosecutor proves that the defendant committed an unlawful homicide, but cannot prove malice, then the defendant is guilty of manslaughter. 

There are three types of manslaughter:

• Voluntary manslaughter
• Involuntary manslaughter
• Vehicular manslaughter

 Voluntary Manslaughter 

Voluntary manslaughter occurs when someone intentionally kills another person, but without malice.  If the defendant intentionally kills another person but did so under circumstances of great provocation or under an honest but unreasonable belief in the need for self-defense or defense of another, then the act was committed without malice. 

Voluntary manslaughter is punishable by 3, 6 or 11 years in state prison. 

Involuntary Manslaughter 

 Involuntary manslaughter is homicide that is unintentional, but criminally negligent. It is punished by a sentence of two, three or four years in county jail. 

Vehicular Manslaughter 

Vehicular manslaughter is homicide committed without malice while operating an automobile or boat. 

Vehicular manslaughter that does not involve intoxication may be punished by up to six years in state prison, if the defendant’s conduct involves gross negligence.  If the defendant was negligent, but not grossly negligent, the offense is a misdemeanor, punishable by up to one year in county jail. 

If a vehicular manslaughter is the result of deliberately causing a traffic collision in order to commit insurance fraud, it is punishable by up to ten years in state prison.  It is also possible that a prosecutor may file a charge of murder under such circumstances, alleging that the act amounts to a conscious disregard for human life, meaning that the defendant acted with implied malice. 

Vehicular manslaughter while intoxicated is punishable by up to ten years in state prison.  In some cases, prosecutors will charge a defendant murder when he or she kills someone in the course of intoxicated driving.  If the prosecutor can prove that a defendant was aware of the high risk to human life that his or her intoxicated driving created, the prosecutor will argue that the defendant acted with malice and is therefore guilty of murder.  The most common example of this argument is when the defendant has been previously convicted of driving under the influence and in the course of that conviction, was advised of the danger of this conduct.