Can a prosecutor vouch for the credibility of a witness?

With respect to vouching, "[a] 'prosecutor is prohibited from vouching for the credibility of witnesses or otherwise bolstering the veracity of their testimony by referring to evidence outside the record. [Citations.] Nor is a prosecutor permitted to place the prestige of [his or] her office behind a witness by offering the impression that [he or] she has taken steps to assure a witness's truthfulness at trial. [Citation.] However, so long as a prosecutor's assurances regarding the apparent honesty or reliability of prosecution witnesses are based on the "facts of [the] record and the inferences reasonably drawn therefrom, rather than any purported personal knowledge or belief," [his or] her comments cannot be characterized as improper vouching.' [Citations.] Misconduct arises only if, in arguing the veracity of a witness, the prosecutor implies [he or] she has evidence about which the jury is unaware." (People v. Fernandez (2013) 216 Cal.App.4th 540, 561.)

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