It's a terrifying prospect; should an intruder attempt to break into your home, the use of lethal force might be the only option to protect you and your family. This topic can be difficult from a legal perspective, as California is without the "Stand Your Ground Law" which is the subject of controversy in so many other states. There are other laws that cover the issue in this state, as explained by abc10.com.
The Castle Doctrine is frequently cited in these cases. This law states that a person may utilize force when faced with a home intrusion. However, the homeowner must have the reasonable belief that he or his family are under the direct threat of death or grievous bodily injury should the intruder be successful. The homeowner must also be aware that the person entered the home illegally and with force. For example, an intruder in the home with a deadly weapon surrounded by evidence of forced entry may satisfy these components.
California also has justifiable homicide laws on record, which apply to a few different circumstances. The Judicial Council of California Criminal Jury Instructions (CALCRIM) states that self-defense is a reasonable defense for homicide in certain cases. The person using deadly force must be under the belief that he is at risk of imminent danger of being killed or gravely injured if he doesn't take the appropriate action. Additionally, the deadly force must not be considered excessive in order for the homicide to be considered justified.
The same justification can be used for issues relating to home defense. Similar to the Castle Doctrine, a homicide may be considered justifiable if an intruder is attempting to force his way into the home to commit a crime. In this case, a defendant is permitted to defend himself and his family, and may also pursue the assailant until the threat of death or severe injury has passed. Threats must be credible and imminent, however. The fear of a future threat that is not explicitly expressed may not be justifiable in this case.