What is the test for instructing a jury in the language of a statutory definition of a crime?

"The language of a statute defining a crime or defense is generally an appropriate and desirable basis for an instruction, and is ordinarily sufficient when the defendant fails to request amplification. If the jury would have no difficulty in understanding the statute without guidance, the court need do no more than instruct in statutory language." (People v. Poggi (1988) 45 Cal.3d 306, 327.) But "'[t]he general rule which provides that in defining the elements of a crime it is enough for the court to instruct in the language of the statute when the defendant fails to request an amplification thereof [citation] will not prevail when the jury would have difficulty in understanding and applying the statute. Under such circumstances, a court must give additional guidance and clarification on its own motion. [Citations.]'" (People v. Rogers (1971) 5 Cal.3d 129, 138.) A trial court's sua sponte obligation to instruct the jury "comes into play when a statutory term 'does not have a plain, unambiguous meaning,' has a 'particular and restricted meaning' [citation], or has a technical meaning peculiar to the law or an area of law [citation]." (People v. Roberge (2003) 29 Cal.4th 979, 988.)

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