A trial courts failure to adequately instruct the jury on the relationship between malice and a good faith defense requires reversal. The defendant was convicted of two counts of being a lawful custodian of his children who maliciously deprived another lawful custodian of the children of her right to custody, in violation of Penal Code section 278.5, subdivision (a). Defendant argued on appeal that the trial court erred by instructing the jury that he had the burden of proving, by a preponderance of the evidence,that he had a good faith and reasonable belief that if left with their mother, the children would suffer immediate bodily injury or emotional harm. (Pen. Code, sec. 278.7, subd. (a).) He argued that the facts supporting the defense negated an element of the crime, i.e., malice, and that he was thereby required to raise only a reasonable doubt as to the existence of those facts. The Court of Appeal agreed, holding that the trial court should have issued a clarifying instruction. The error was prejudicial and required reversal.