Although record fails to show trial court advised mentally disordered offender (MDO) of jury trial right, the error was harmless. Defendant was subject to commitment proceedings under the Mentally Disordered Offender Act (Act) (Pen. Code, § 2960 et seq.). The Act accords a right to jury trial “unless waived by the person and the district attorney” (Pen. Code, §§ 2966, subd. (b); 2972, subd. (a)). The MDO claimed his attorney’s jury waiver was ineffective to waive his rights. Held: Affirmed. The jury waiver provision of the Act does not require a personal waiver from the MDO or give defense counsel exclusive control. Counsel may waive jury at the direction of the MDO or with his or her consent; when the MDO is incompetent to make the determination, counsel may waive a jury, even over the MDO’s objection. The validity of counsel’s jury waiver hinges on whether the MDO knew of his or her jury trial right and directed and/or consented to counsel’s waiver. In this case, a settled statement established that trial counsel waived a jury in chambers. It may be presumed that defense counsel discussed all pertinent matters with the MDO and informed him of his rights, thus, the failure to expressly advise the MDO of his rights was harmless error. However, as a general rule, when an MDO matter is tried by the court and the MDO did not personally waive a jury, the record must contain an express, valid jury advisement and waiver. If the court is unable to so advise the MDO, the record should reflect the MDO was made aware of his jury trial right before counsel waived it.