In California, Penal Code section 187 defines murder as the unlawful killing of a human being, or a fetus, with malice aforethought. Malice in the intent to do evil. The malice may be express or implied. It is express when there is manifested a deliberate intention unlawfully to take away the life of a fellow creature. It is implied, when no considerable provocation appears, or when the circumstances attending the killing show an abandoned and malignant heart.
Manslaughter is the unlawful killing of a human being without malice. There are three kinds:
(a) Voluntary--upon a sudden quarrel or heat of passion.
(b) Involuntary--in the commission of an unlawful act, not amounting to felony; or in the commission of a lawful act which might produce death, in an unlawful manner, or without due caution and circumspection. This subdivision shall not apply to acts committed in the driving of a vehicle.
If charged with a serious crime, our State Bar Certified Criminal Law Specialist can help. 213 250 9100