California Code, Probate Code - PROB § 1543

(a) If the petition as filed or as amended states that an adoption petition has been filed, a report with respect to the suitability of the proposed guardian for guardianship shall be filed with the court by the agency investigating the adoption. In other cases, the local agency designated by the board of supervisors to provide public social services shall file a report with the court with respect to the proposed guardian of the same character required to be made with regard to an applicant for foster family home licensure, or, on and after January 1, 2020, resource family approval, as described in Section 16519.5 of the Welfare and Institutions Code.

(b) The report filed with the court pursuant to this section is confidential. The report may be considered by the court and shall be made available only to the persons who have been served in the proceeding and the persons who have appeared in the proceeding or their attorneys. The report may be received in evidence upon stipulation of counsel for all of those persons who are present at the hearing or, if a person is present at the hearing but is not represented by counsel, upon consent of that person.