Can a juror's post-trial statements be used as evidence in a criminal case?

The court misapprehended the scope of subdivision (a) of Evidence Code section 1150, which bars admitting evidence showing the effect of statements or events on the mental processes of a juror, but does permit admitting "any otherwise admissible evidence" to show that statements were made or events occurred. Thus, even if the juror's posttrial statements were not themselves misconduct, arguably they provided a basis for permitting defendant to investigate whether the jury discussed the improper subject of deterrence during deliberations. (See People v. Perez (1992) 4 Cal.App.4th 893, 908, 6 Cal.Rptr.2d 141 [jury misconduct to disregard trial court's express instruction not to consider defendant's failure to testify].)