When a defendant challenges on appeal a motion for a new trial on grounds of juror misconduct, does he accept the credibility determinations and findings of the trial court?

When a defendant challenges on appeal a trial court's denial of his motion for a new trial on grounds of juror misconduct, "[w]e accept the trial court's credibility determinations and findings on questions of historical fact if supported by substantial evidence[;]" the question of "[w]hether prejudice arose from juror misconduct, however, is a mixed question of law and fact subject to an appellate court's independent determination." (People v. Nesler (1997) 16 Cal.4th 561, 582.) Essentially, the question of whether misconduct actually occurred is reviewed for substantial evidence, while the question of whether any misconduct was prejudicial is subject to independent review.