What is the legal test for reversal of a jury verdict when a prosecutor's cross-examination is prejudicial?

"Prosecutorial [error] requires reversal when it 'so infect[s] a trial with unfairness [as to] create a denial of due process. [Citations.] Conduct by a prosecutor that does not reach that level nevertheless constitutes [error] under state law, but only if it involves the use of deceptive or reprehensible methods to persuade the court or jury.' " (People v. Armstrong (2019) 6 Cal.5th 735, 795.) If error is found under state law, reversal is not required unless it is reasonably probable that the error contributed to the verdict. (People v. Martinez (2010) 47 Cal.4th 911, 957.) Defendant has failed to meet either standard.

While, "[e]ffective and legitimate cross-examination may involve assertive and even harsh questioning" (People v. Armstrong, supra, 6 Cal.5th at p. 796), it may not be argumentative. " 'An argumentative question is a speech to the jury masquerading as a question. . . . An argumentative question that essentially talks past the witness, and makes an argument to the jury, is improper because it does not seek to elicit relevant, competent testimony . . . .' " (Id. at p. 796, fn. 23.) We agree the portions of the prosecutor's cross-examination challenged by defendant were largely argumentative and thus inappropriate. We, however, conclude they were not prejudicial.