What is the legal test for waiving a jury in a criminal case?

Article I, section 16 of the California Constitution provides, in relevant part, that "[a] jury may be waived in a criminal cause by the consent of both parties expressed in open court by the defendant and the defendant's counsel." Our Supreme Court has instructed that "[t]he requirement that a defendant and defense counsel personally and expressly waive the right to jury trial describes the manner in which a criminal defendant who wishes to waive this 'inviolate' right may do so, and constitutes the only method by which the constitutional right to jury trial may be waived in a criminal case." (People v. Vera (1997) 15 Cal.4th 269, 278.)

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