Testimonial Evidence CA

Question 1

Competency of Witnesses

Answer 1

BOTH Federal and California law:
The witnesses must testify based on personal knowledge and to take an oath or make an affirmation to tell the truth.

CA ONLY: The witness also must understand their legal duty to tell the truth.

Question 2

Hypnosis

Answer 2

CA ONLY
A witness who has been hypnotized to restore their memory is only competent to testify about matters that they recalled and related to others prior to the hypnosis.

Additional requirements in criminal cases: (1) the substance of the prehypnotic memory must have been preserved in a writing or recording prior to the hypnosis, (2) the hypnosis must have been video recorded, and (3) the hypnosis must have been done outside of the presence of law enforcement, the prosecution, and the defense.

Question 3

Dead Man Acts

Answer 3

Make an interested person incompetent to testify to a personal transaction or communication with a deceased, when such testimony is offered against the representative or successors in interest of the deceased.

California does not have a Dead Man Act.

Question 4

Refreshing Witness’ Recollection

Answer 4

FEDERAL: If the witness refreshed their memory
while on the stand, an adverse party is entitled to have the writing produced at trial and to use and introduce relevant portions. If the witness refreshed their memory before trial, it is within the court’s discretion to require production.

CA: Does not matter when the refreshing was done. If the opponent asks for the writing to be produced, the proponent must produce it (unless they do not have it and cannot obtain it by subpoena or other means)

Question 5

Determining Reliability of an Expert Witness and Scientific Opinions

Answer 5

BOTH Federal and CA:
Expert witness’s opinion must be based on reliable principles and methods that are reliably applied to the facts.

FEDERAL Standard
Courts consider various factors when determining the reliability of scientific AND non-scientific opinions: Whether the expert’s theory has been tested
- Whether it has been subject to peer review
- Any known or potential error rate
- Any standards controlling its operation
- Whether it is generally accepted in the relevant field

CALIFORNIA Standard
The scientific opinion must be based on principles that are generally accepted by experts in the field.

This standard does not apply to non-scientific opinions and medical opinions, the reliability of which is based on the facts and circumstances of the case.

Question 6

Learned Treatise Hearsay Exception

Answer 6

FEDERAL: Once established as an accepted authority in the field, a learned treatise that is relied upon by an expert on cross-examination is admissible to prove any facts contained in the treatise

CALIFORNIA: A learned treatise is admissible only to show “facts of general notoriety or interest” found in published maps or charts, or in books of history, science, or art.

Takeaway: A learned treatise is usually admissible only on cross-examination of an expert witness. Narrow hearsay exception.

Question 7

Motions to Sequester Witnesses

Answer 7

FEDERAL RULES: If a party makes a motion to sequester a witness (i.e., exclude them from the courtroom) the judge MUST grant the motion.

CALIFORNIA: The judge has DISCRETION to grant or deny a party’s motion to sequester

In both cases, the judge must not exclude: (1) a party or a designated officer or employee of a party, (2) a person whose presence is essential to the presentation of a party’s claim or defense, or (3) a person statutorily authorized to be present.