The crime of battery is governed by California Penal Code Sections 242 and 243. Battery is defined as "any willful and unlawful use of force or violence upon the person of another." (PC 242) Battery is defined as "simple" battery and battery with serious injury. The punishments
Before a jury deliberates, the jury is read "jury instructions" by the judge, defining the rules of law that must govern their decisions as to guilt or innocence. The California criminal jury instructions (CALJIC) define battery.
Simple Battery
CALJIC 16.140 defines the elements that must be proved to make a finding of battery. This means that where these elements are not so proved, there cannot be a finding of guilty. The elements are:
"1. A person used force or violence upon the person of another; and
2. The use was willful [and unlawful]."
Simple battery is a misdemeanor, punishable by a fine up to $2,000 or by imprisonment in a county jail up to 6 months, or by both fine and imprisonment.
Battery with Serious Bodily Injury
CALJIC 9.12: Battery with Serious Bodily Injury is defined as:
"Every person who willfully and unlawfully uses any force or violence upon the person of another resulting in the infliction of serious bodily injury, is guilty of the crime of battery with serious bodily injury in violation of Penal Code section 243, subdivision (d) of the Penal Code."
When a battery is committed against any person, resulting in serious bodily injury, the battery is punishable by imprisonment in the county jail not exceeding one year or imprisonment in the state prison for 2, 3, or 4 years. This means that this crime is a "wobbler," so named because it can be prosecuted and punished as either a misdemeanor or a felony.
Defenses
The use of lawful self-defense or defense of others may be used against a charge of either degree of battery. Where one reasonably believes that they are facing imminent bodily injury, they are allowed to defend themselves with the enough of a degree of force to ward off the imminent injury. Thus, this would make it lawful self-defense. The standard utilized is that of reasonableness. It must be reasonable, by an objective person's standard, that the threat was there and the means used was reasonable.
Battery is a general intent crime, meaning that the person committing the battery must intend their own actions, independent of the outcome. For example, if a person commits a battery, such as socking someone in the face in a fight, but misses the intended target and hits a bystander, then his original intended action of throwing the punch is all that is needed to make a finding of battery. But if the person reasonably believed that using his arm and fist to sock someone was necessary in order to avoid imminent physical injury, then the battery charge is incorrect because the force used was lawful.
The burden of proof in a battery case belongs to the prosecution. The prosecution must make a finding of guilty beyond a reasonable doubt. If the jury finds reasonable doubt in the defense's theory of self-defense, then the judge will instruct the jury that they must make a finding of not guilty.