What is the state of the law on the credibility of jurors in a civil case?

We defer to the trial court's determination of the jurors' credibility and reject defendant's speculation that the jurors lied. Defendant also argues that an unnamed juror's frustration with the length of the trial demonstrated a negative attitude of all the jurors caused by the cartoon (rather than simply the length of the trial, apparently). Speculation cannot establish prejudice. (People v. Williams (1988) 44 Cal.3d 883, 933.)