On what basis can a jury be found guilty of misconduct in their deliberations?

On the other hand, the Rhodes court noted, there exists a strong public interest in the ascertainment of truth in judicial proceedings, including jury deliberations, which necessarily means that a verdict reached by prejudicial juror misconduct must not be permitted to stand. "Lifting the veil of postverdict secrecy to expose juror misconduct" would tend to diminish such practices and "purify the jury room" by rendering "such improprieties capable and probable of exposure, and consequently deterring jurors from resorting to them." (People v. Rhodes, supra, 212 Cal.App.3d at pp. 549-550, 261 Cal.Rptr. 1, internal quotation marks omitted.)