In People v. Lapenias (2021) 67 Cal.App.5th 162 an expert testified regarding CSAAS, a theory that identifies typical behaviors of sexually abused children. The expert had no information or knowledge about the facts of the instant case. Defense counsel did not cross-examine the expert. Instead, after an off-the-record sidebar, the trial court read aloud five written questions submitted by individual jurors. One juror asked: “Is it common for children to make up a story that abuse occurred, when, in fact it did not?” Over defendant’s objection, the expert responded: “No, that’s rare.” Defense counsel repeated his objection, arguing that the question asked the expert to evaluate defendant’s guilt.
The reviewing court agreed with defense counsel. An expert may not give an opinion as to whether another witness is telling the truth, or whether the defendant is guilty, because the jury is generally well equipped to discern whether a witness is being truthful. As in People v. Julian (2019) 34 Cal.App.5th 878 and People v. Wilson (2019) 33 Cal.App.5th 559, the CSAAS expert’s statement here was inadmissible, as it amounted to vouching for the veracity of the alleged victim.
