"The testimony of an in-custody informant should be viewed with caution and close scrutiny. In evaluating such testimony, you should consider the extent to which it may have been influenced by the receipt of, or expectation of, any benefits from the party calling that witness. This does not mean that you may arbitrarily disregard such testimony, but you should give it the weight to which you find it to be entitled in the light of all the evidence in the case."
The statement filed with the court shall not expand or limit the defendant's right to discover information that is otherwise provided by law. The statement shall be provided to the defendant or the defendant's attorney prior to trial and the information contained in the statement shall be subject to rules of evidence.
Ca. Pen. Code § 1127a