Can a juror's interpretation of their instructions be impeached under California Evidence Code section 1150?

We agree with the People that the trial court acted within its discretion in concluding that the entire contents of juror No. 12's declaration was inadmissible to impeach the verdict under Evidence Code section 1150, because it reflected the jury's mental processes during its deliberations. First, as the court noted, the declaration did "not establish that the juror was laboring under any erroneous definition of reasonable doubt or the burden of proof. They merely show during the process of deliberations jurors who were inclined to vote not guilty were asked to justify why any doubt they had was unreasonable in light of the evidence." This give and take between the jurors requiring that they support their opinions with evidence is the precise area from which the law excludes intrusion. Even to the extent that the juror's declaration could be deemed conclusive proof of the foreperson's erroneous understanding of the court's instructions, it would remain inadmissible. (People v. Elkins (1981) 123 Cal.App.3d 632, 636-637 [juror's misinterpretation of court's instructions inadmissible to impeach verdict because

Page 12