Under the California Constitution, trial by jury is an inviolate right and shall be secured to all. (Enyart v. City of Los Angeles (1999) 76 Cal.App.4th 499, 506.) The right to trial by jury includes the right to twelve impartial jurors. (Id.) An impartial jury is one in which no member has been improperly influenced and every member is capable and willing to decide the case solely on the evidence before it. (In re Hamilton (1999) 20 Cal.4th 273, 294.)

Jury misconduct can form the basis of a motion for a new trial. (Code of Civ.Proc., § 657(2).) Juror misconduct involves juror prejudice or bias. (Evid. Code, § 1150.) A motion for a new trial may be granted if juror misconduct “materially affected the substantial rights of a party.” (Ovando v. County of Los Angeles (2008) 159 Cal.App.4th 42, 57.)

Legal Standard

“A motion for new trial is a creature of statute.” (Neal v. Montgomery Elevator Co. (1992) 7 Cal. App. 4th 1194, 1198.) A motion for new trial may be granted if there is any “[m]isconduct of the jury; and whenever any one or more of the jurors have been induced to assent to any general or special verdict, or to a finding on any question submitted to them by the court, by a resort to the determination of chance, such misconduct may be proved by the affidavit of any one of the jurors.” (Code of Civ. Proc., § 657.)

“The moving party bears the burden of establishing juror misconduct. (Code of Civ. Proc., § 657(2); People v. Duran (1996) 50 Cal.App.4th 103, 113, 57 Cal.Rptr.2d 635; Barboni v. Tuomi (2012) 210 Cal.App.4th 340, 349.) Unless the prevailing party rebuts the presumption by showing the misconduct was harmless, a new trial should be granted. (Enyart v. City of Los Angeles (1999) 76 Cal.App.4th 499, 507)

In ruling on a request for a new trial based on jury misconduct, the trial court must undertake a three-step inquiry. (Whitlock v. Foster Wheeler, LLC (2008) 160 Cal.App.4th 149, 160; Barboni v. Tuomi (2012) 210 Cal.App.4th 340, 345.) First, the trial court must determine whether the affidavits supporting the motion are admissible. (Id.) Second, if the evidence is admissible, the trial court must determine whether the facts establish misconduct. (Id.) Third, assuming misconduct, the trial court must determine whether the misconduct was prejudicial. (Id.) “A trial court has broad discretion in ruling on each of these issues, and its rulings will not be disturbed absent a clear abuse of discretion.” (Id.)

First Step: Admissibility of Affidavits

“Upon an inquiry as to the validity of a verdict, any otherwise admissible evidence may be received as to statements made, or conduct, conditions, or events occurring, either within or without the jury room, of such a character as is likely to have influenced the verdict improperly. No evidence is admissible to show the effect of such statement, conduct, condition, or event upon a juror either in influencing him to assent to or dissent from the verdict or concerning the mental processes by which it was determined.” (Evid. Code, § 1150(a).)

This statute distinguishes between “proof of overt acts, objectively ascertainable, and proof of the subjective reasoning processes of the individual juror, which can be neither corroborated nor disproved.” (Enyart v. City of Los Angeles (1999) 76 Cal.App.4th 499, 506.) While “jurors may testify to ‘overt acts’--that is, such statements, conduct, conditions, or events as are ‘open to sight, hearing, and the other senses and thus subject to corroboration’--[they] may not testify to ‘the subjective reasoning processes of the individual juror.’” (In re Stankewitz (1985) 40 Cal.3d 391, 398.) Likewise, evidence about a jury's “subjective collective mental process purporting to show how the verdict was reached” is inadmissible to impeach a jury verdict. (Ford v. Bennacka (1990) 226 Cal.App.3d 330, 336.) In other words, “evidence that the internal thought processes of one or more jurors were biased is not admissible to impeach a verdict.” (Donovan v. Poway Unified School Dist. (2008) 167 Cal.App.4th 567, 625.)

Second Step: Juror Misconduct

“The concealment during voir dire of a bias, belief or state of mind which prevents a juror from following the court's instructions and acting in an impartial manner constitutes misconduct.” (Tapia v. Barker (1984) 160 Cal.App.3d 761, 765.) In determining whether misconduct exists, the trial court must assess the credibility of the declarants and is entitled to believe one over the other. (Toste v. CalPortland Construction (2016) 245 Cal.App.4th 362, 372.)

“Presentation to or reception by a jury of new evidence from sources outside the trial evidence constitutes misconduct.” (Whitlock v. Foster Wheeler, LLC (2008) 160 Cal.App.4th 149, 161.)

If no affidavits or declarations are introduced to counter the evidence of jury misconduct, the acts are deemed established and the only issue is whether they are harmful or prejudicial. (Tapia v. Barker (1984) 160 Cal.App.3d 761, 766.)

Third Step: Prejudice

Misconduct was prejudicial if there is a substantial likelihood that the juror was biased and that the misconduct affected the verdict. (Ovando v. County of Los Angeles (2008) 159 Cal.App.4th 42, 58.) Juror misconduct raises a presumption of prejudice, and unless the prevailing party rebuts the presumption by showing the misconduct was harmless, a new trial should be granted. (Enyart v. City of Los Angeles (1999) 76 Cal.App.4th 499, 507.)

“The presumption of prejudice is an evidentiary aid to those parties who are able to establish serious misconduct of a type likely to have had an effect on the verdict or which deprived the complaining party of thorough consideration of his case, yet who are unable to establish by a preponderance of the evidence that actual prejudice occurred. The law thus recognizes the substantial barrier to proof of prejudice which section 1150 erects, and it seeks to lower that barrier somewhat.” (Hasson v. Ford Motor Co. (1982) 32 Cal.3d 388, 416; see also Evid. Code § 1150.)

This presumption may be rebutted by an affirmative evidentiary showing that prejudice does not exist based upon a consideration of such factors as the strength of the evidence that misconduct occurred, the nature and seriousness of the misconduct, and the probability that actual prejudice may have ensued. (Whitlock v. Foster Wheeler, LLC (2008) 160 Cal.App.4th 149, 162.) “[S]ince the trial judge had all the evidence before him on the merits of the case, and as well the affidavits, he was in the best position to evaluate the prejudicial effect of the alleged misconduct.” (Id.)

Experiments

“There is an abundance of reported decisions concerning jury experiments. The classic rule was stated by our Supreme Court early in this century: ‘They [the jurors] may carry out experiments within the lines of offered evidence, but if their experiments shall invade new fields and they shall be influenced in their verdict by discoveries from such experiments which will not fall fairly within the scope and purview of the evidence, then manifestly, the jury has been itself taking evidence without the knowledge of either party, evidence which it is not possible for the party injured to meet, answer, or explain.’” (Bell v. State of California (1998) 63 Cal.App.4th 919, 931.)

Thus, experiments carried out privately by jurors qualify as juror misconduct. (Id. at 931.) “Jurors cannot be permitted to investigate the case outside the courtroom. They must describe the guilt or innocence of the defendant upon the evidence introduced at the trial. It is impossible for this court to say that the outside investigation did not affect the result as to the character for the verdict rendered. For when misconduct of jurors is shown, it is presumed to be injurious to defendant, unless the contrary appears.” (Id.) “What jurors can do, as a body during deliberations, is engage in experiments which amount to no more than a careful evaluation of the evidence which was presented at trial.” (Id. at 932.)