187. (a) Murder is the unlawful killing of a human being, or a fetus, with malice aforethought. (b) This section shall not apply to any person who commits an act that results in the death of a fetus if any of the following apply: (1) The act complied with the Therapeutic Abortion Act, Article 2 (commencing with Section 123400) of Chapter 2 of Part 2 of Division 106 of the Health and Safety Code. (2) The act was committed by a holder of a physician's and surgeon' s certificate, as defined in the Business and Professions Code, in a case where, to a medical certainty, the result of childbirth would be death of the mother of the fetus or where her death from childbirth, although not medically certain, would be substantially certain or more likely than not. (3) The act was solicited, aided, abetted, or consented to by the mother of the fetus. (c) Subdivision (b) shall not be construed to prohibit the prosecution of any person under any other provision of law.
188. Such 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. When it is shown that the killing resulted from the intentional doing of an act with express or implied malice as defined above, no other mental state need be shown to establish the mental state of malice aforethought. Neither an awareness of the obligation to act within the general body of laws regulating society nor acting despite such awareness is included within the definition of malice.
189. All murder which is perpetrated by means of a destructive device or explosive, a weapon of mass destruction, knowing use of ammunition designed primarily to penetrate metal or armor, poison, lying in wait, torture, or by any other kind of willful, deliberate, and premeditated killing, or which is committed in the perpetration of, or attempt to perpetrate, arson, rape, carjacking, robbery, burglary, mayhem, kidnapping, train wrecking, or any act punishable under Section 206, 286, 288, 288a, or 289, or any murder which is perpetrated by means of discharging a firearm from a motor vehicle, intentionally at another person outside of the vehicle with the intent to inflict death, is murder of the first degree. All other kinds of murders are of the second degree. As used in this section, "destructive device" means any destructive device as defined in Section 12301, and "explosive" means any explosive as defined in Section 12000 of the Health and Safety Code. As used in this section, "weapon of mass destruction" means any item defined in Section 11417. To prove the killing was "deliberate and premeditated," it shall not be necessary to prove the defendant maturely and meaningfully reflected upon the gravity of his or her act.
189.5. (a) Upon a trial for murder, the commission of the homicide by the defendant being proved, the burden of proving circumstances of mitigation, or that justify or excuse it, devolves upon the defendant, unless the proof on the part of the prosecution tends to show that the crime committed only amounts to manslaughter, or that the defendant was justifiable or excusable. (b) Nothing in this section shall apply to or affect any proceeding under Section 190.3 or 190.4.
190. (a) Every person guilty of murder in the first degree shall be punished by death, imprisonment in the state prison for life without the possibility of parole, or imprisonment in the state prison for a term of 25 years to life.