Sharp

When the defendant in a criminal action has placed his or her mental state at issue through the proposed testimony of a mental health expert, Penal Code section 1054.3, subdivision (b)(1) authorizes the trial court to order the defendant to submit to examination by an expert retained by the prosecution. In this case, we decide whether that statutory authority extends to a defendant who has pleaded not guilty by reason of insanity (NGI) and proposes to call a mental health expert on the issue of sanity. (See § 1027.)

We conclude section 1054.3, subdivision (b)(1) (hereafter section 1054.3(b)(1)) does apply in these circumstances. By its terms, the statute authorizes an order compelling examination by a prosecution-retained expert “whenever ... at any phase of the criminal action” the defense has proposed its own expert testimony on mental state, “[u]nless otherwise specifically addressed by an existing provision of law.” (Italics added.) Section 1027, which governs the adjudication of an NGI plea, specifically addresses the defendant’s examination by court-appointed experts, but not by prosecution-retained experts, the subject of section 1054.3(b)(1). The exception in…