Cal. Evidence Code § 776

(a) A party to the record of any civil action, or a person identified with such a party, may be called and examined as if under cross-examination by any adverse party at any time during the presentation of evidence by the party calling the witness. (b) A witness examined by a party under this section may be cross-examined by all other parties to the action in such order as the court directs; but, subject to subdivision (e), the witness may be examined only as if under redirect examination by: (1) In the case of a witness who is a party, his own counsel and counsel for a party who is not adverse to the witness. (2) In the case of a witness who is not a party, counsel for the party with whom the witness is identified and counsel for a party who is not adverse to the party with whom the witness is identified. (c) For the purpose of this section, parties represented by the same counsel are deemed to be a single party. (d) For the purpose of this section, a person is identified with a party if he is: (1) A person for whose immediate benefit the action is prosecuted or defended by the party. (2) A director, officer, superintendent, member, agent, employee, or managing agent of the party or of a person specified in paragraph (1), or any public employee of a public entity when such public entity is the party. (3) A person who was in any of the relationships specified in paragraph (2) at the time of the act or omission giving rise to the cause of action. (4) A person who was in any of the relationships specified in paragraph (2) at the time he obtained knowledge of the matter concerning which he is sought to be examined under this section. (e) Paragraph (2) of subdivision (b) does not require counsel for the party with whom the witness is identified and counsel for a party who is not adverse to the party with whom the witness is identified to examine the witness as if under redirect examination if the party who called the witness for examination under this section: (1) Is also a person identified with the same party with whom the witness is identified. (2) Is the personal representative, heir, successor, or assignee of a person identified with the same party with whom the witness is identified.