CALIFORNIA EVIDENCE: CIVIL AND CRIMINAL
...Opinion & Scientific Evidence
......Expert Testimony: In General
.........Things Expert May Rely On
............Personal Observation
4 Cards On This Topic:

O's testimony as to D's seeming emotional episodes during interview was relevant to help the jury determine D's intent at the time of the events, his state of mind thereafter, and his credibility.

EC 702 provision that testimony of witness inadmissible unless based on personal knowledge by its terms does not apply to an expert testifying per EC 801.

Court properly allowed testimony re E's study on people who committed serious crimes as foundational to his opinion regarding D himself.

Expert opinion must be based upon facts derived from personal observation or hypotheses finding support in evidence or other means subject to proof.