California Penal Code 187(a): Murder Degrees, Penalties, Defenses

California Penal Code Section 187(a) defines murder as the unlawful killing of a human being, or a fetus, with malice aforethought. That single sentence is the foundation of every murder prosecution in the state. The degree of the charge, the sentencing range, and whether a defendant faces life without parole or even the death penalty are all set by separate statutes that build on top of 187(a). Sentences run from 15 years to life at the low end to life without the possibility of parole or death at the high end.¹

What the Statute Covers

Section 187(a) protects two categories of victim: a human being and a fetus. Including the fetus means that an attack on a pregnant person causing the death of the unborn child can support a murder charge for that death on its own, separate from any charge involving the mother.¹

The statute carves out three exceptions where the death of a fetus is not murder. Lawful abortions performed under California’s Reproductive Privacy Act are excluded. So are cases where a licensed physician determines that childbirth would cause the pregnant person’s death. And the pregnant person cannot be prosecuted for their own actions or choices regarding the pregnancy.¹

Malice Aforethought

Malice aforethought is the mental state that turns an unlawful killing into murder rather than manslaughter. It sounds like it requires hatred or long planning. It does not. California recognizes two forms, and either is enough.

Express malice means the defendant deliberately intended to kill. The person wanted the victim dead and acted on that intention.²

Implied malice applies when the defendant did not set out to kill but acted in a way so dangerous that death was a foreseeable result, and did it knowing the risk. The classic phrase is “an abandoned and malignant heart,” which comes down to a conscious choice to disregard a known threat to human life.²

Senate Bill 1437, enacted in 2019, added an important limit: malice cannot be imputed to a person based solely on their participation in a crime. Before the reform, accomplices in certain felonies could be convicted of murder without any personal intent to kill. That is no longer the law.²

First-Degree Murder

Penal Code 189 separates murder into two degrees. A killing is first-degree murder if any of three things is true: it was premeditated, it was carried out by a specifically dangerous method, or it happened during one of several qualifying felonies.

Premeditation

A planned killing is first-degree murder. The planning time does not need to be long. Courts have found premeditation even when the decision was made in moments, as long as the evidence shows the defendant actually weighed the choice rather than acting on pure impulse.³

Specific Methods

Certain methods trigger first-degree murder automatically. These include explosives or destructive devices, weapons of mass destruction, armor-piercing ammunition, poison, torture, and lying in wait. Intentionally shooting from a moving vehicle also qualifies.³

Felony Murder

A death that occurs during the commission of certain dangerous felonies can support a first-degree murder charge. Qualifying felonies include arson, rape, carjacking, robbery, burglary, mayhem, kidnapping, and train wrecking, among others.³

SB 1437 narrowed who can be convicted under this theory. A participant in a qualifying felony where someone dies can only be convicted of murder if one of three things is true:

The person was the actual killer.
The person was not the killer but aided or encouraged the killing with the specific intent that someone die.
The person was a major participant in the underlying felony and acted with reckless indifference to human life.

That third category drives most of the courtroom fights. Whether someone qualifies as a “major participant” acting with “reckless indifference” turns on fact-intensive questions like awareness of weapons, opportunity to prevent the killing, and how central the defendant was to the planning.³

One exception: when the victim is a peace officer killed in the line of duty and the defendant knew or should have known the victim was an officer, the older, broader felony murder rule still applies.³

Second-Degree Murder

Any murder that does not qualify as first-degree is second-degree. In practice, this usually means killings committed with implied malice but without premeditation and without a qualifying felony. The defendant did something extremely dangerous, knew it could kill, and went ahead anyway.³

Watson Murder: DUI Killings

The best-known use of implied-malice second-degree murder comes from the 1981 California Supreme Court case People v. Watson. The court held that a drunk driver who kills another person can face second-degree murder, not just manslaughter, when the evidence supports implied malice.⁴

Prosecutors pursuing a Watson murder charge typically point to a prior DUI conviction and a formal advisement, signed at the earlier sentencing, warning the defendant that driving drunk can kill. That prior warning makes it much harder for the defense to argue the driver did not understand the danger.

Murder vs. Manslaughter

The line between murder and manslaughter is malice. Manslaughter is an unlawful killing without malice aforethought. California recognizes two main types. Voluntary manslaughter covers killings in the heat of passion or during a sudden quarrel, where provocation would cause a reasonable person to lose control. Involuntary manslaughter covers deaths caused by criminal negligence or during a low-level unlawful act that is not a felony.⁵

Imperfect Self-Defense

One of the most common ways a murder charge gets reduced to voluntary manslaughter is imperfect self-defense. It applies when the defendant genuinely believed they faced an imminent threat of death or serious injury and that deadly force was necessary, but at least one of those beliefs was unreasonable. The honest but mistaken belief negates malice, dropping the charge to voluntary manslaughter. The burden sits with the prosecution to disprove it beyond a reasonable doubt.⁶

Penalties

Sentencing depends on the degree of murder and the circumstances surrounding the killing.

First-Degree Murder

A standard first-degree murder conviction carries 25 years to life in state prison. The 25 years is the minimum time served before a parole hearing becomes possible, not a release date, and release is often denied.⁷

Second-Degree Murder

The base term is 15 years to life. Several circumstances raise it. Killing a peace officer in the line of duty makes the minimum 25 years to life. If the defendant intentionally targeted the officer or used a firearm, the sentence rises to life without parole. A drive-by shooting resulting in death carries 20 years to life.⁷

Special Circumstances

When prosecutors prove special circumstances under Penal Code 190.2, first-degree murder becomes punishable by life without the possibility of parole or death. The statute lists more than 20 qualifying circumstances. Common ones include:

Killing for financial gain.
Multiple murders charged in the same proceeding.
Killing a peace officer or federal agent in the line of duty, where the defendant knew or should have known the victim’s status.
Hate-motivated killings based on race, religion, nationality, gender, sexual orientation, or disability.
Killings carried out to further the activities of a criminal street gang.

A conviction with a proven special circumstance removes any possibility of future release.⁸

The death penalty remains on the books, but Governor Gavin Newsom issued an executive order in 2019 placing a moratorium on executions, withdrawing the state’s lethal injection protocol, and closing the execution chamber at San Quentin. No execution has been carried out since, and the moratorium is still in effect.⁹

Sentencing Enhancements

Enhancements are served consecutively, meaning on top of the base sentence rather than at the same time. Three come up most often in murder cases.

Firearm Enhancements (10-20-Life)

Penal Code 12022.53 adds mandatory prison time when a firearm is used in a qualifying felony, including murder:

Personal use of a firearm: 10 additional years. The gun does not need to be loaded or operable.
Intentionally firing a gun: 20 additional years.
Firing a gun that causes great bodily injury or death: 25 years to life.

A defendant convicted of first-degree murder who also fired the fatal shot faces a minimum of 50 years to life, which is 25 for the murder plus 25 for the enhancement.¹⁰

Gang Enhancement

A murder committed to benefit a criminal street gang adds 10 years under Penal Code 186.22, because murder is classified as a violent felony.¹¹

Three Strikes

Under Penal Code 667, a defendant with one prior strike has the minimum term for the current offense doubled. Two or more prior strikes produce an indeterminate life term with a minimum of at least 25 years before parole eligibility.¹²

Common Defenses

A murder charge is not a conviction. Several defenses can eliminate or reduce liability, and they shape plea negotiations as much as trial outcomes.

Self-Defense and Defense of Others

California treats a killing as justifiable when it is committed in defense of yourself or another against someone attempting murder, a felony, or serious bodily injury. The threat must be immediate and the force must be proportional. The same protection extends to defending your home against someone clearly trying to break in with violent intent.¹³

Excusable Homicide

A killing that happens by accident during lawful activity, without any intent to harm, is excusable. The defense also covers accidental deaths during a sudden fight, provided no unfair advantage was taken and no dangerous weapon was used.

Insanity

California uses the M’Naghten test. The defendant must show that at the time of the killing, a severe mental disease left them unable to understand what they were doing or to know it was wrong. Defendants are presumed sane, so the burden is on the defense. A successful insanity verdict results in commitment to a state mental hospital rather than release.

What “To Life” Actually Means for Parole

For sentences expressed as a term of years “to life,” the minimum term sets the earliest possible parole hearing, not a release date. The California Board of Parole Hearings decides whether the inmate still poses an unreasonable risk of danger to the public, weighing things like disciplinary record, remorse, insight into the crime, and realistic release plans against the severity of the offense and any history of violence.¹⁴

If parole is denied, the next hearing can be set anywhere from 3 to 15 years out. For murder convictions, the Governor of California can reverse or modify the board’s decision, which is one more layer of review before anyone convicted of murder is released.¹⁴

No Statute of Limitations

Murder charges in California can be filed at any time. Under Penal Code 799, there is no statute of limitations for offenses punishable by death or life imprisonment, and both degrees of murder carry life sentences. Cold cases solved through DNA evidence or new witness testimony regularly produce prosecutions decades after the killing.

1
California Legislative Information. California Penal Code 187
2
California Legislative Information. California Penal Code 188
3
California Legislative Information. California Penal Code 189
4
Justia Law. People v. Watson
5
California Legislative Information. California Penal Code 192
6
Justia. CALCRIM No. 571 – Voluntary Manslaughter: Imperfect Self-Defense
7
California Legislative Information. California Penal Code 190
8
California Legislative Information. California Penal Code 190.2
9
Office of Governor Gavin Newsom. Governor Gavin Newsom Orders a Halt to the Death Penalty in California
10
California Legislative Information. California Penal Code 12022.53
11
California Legislative Information. California Penal Code 186.22
12
California Legislative Information. California Penal Code 667
13
California Legislative Information. California Penal Code 197
14
California Department of Corrections and Rehabilitation. Lifer Parole Process