I am not an Arizona attorney, but their Rule 615 is similar to the federal rule. I would think a testifying "expert" on her mental state would be considered essential to counsel in presenting their case. Remember, this is a DP case. There may be AZ case law on this, but I don't have the ability to research that right now. Further, the alleged statement of the brother was not trial testimony. A mental health expert would certainly be expected to review all available evidence (which Samuels did NOT). His failure to interview the family is an egregious error on his part. But I don't think he violated the "rule" by accessing an alleged interview with her brother. I suspect this will be the subject of a number of the jury questions, and JM will question him about it too.