Can a defendant waive his right to be absent from an evidentiary proceeding?

The court then excused the jury to take up defendant's absence request, as it had promised to do. The court explained that defendant had an absolute right to be present during evidentiary proceedings, but that under People v. Robertson (1989) 48 Cal.3d 18, 255 Cal.Rptr. 631, 767 P.2d 1109 (then recently decided), he could make a knowing and voluntary waiver of that right. The court ruled it would excuse defendant from each day's proceedings if, for each such day, defendant executed a separate written waiver of his right to be present.