Cal. Penal Code § 4803

When an application is made to the Governor for pardon or commutation of sentence, or when an application has been referred to the Board of Parole Hearings, the Governor or the board may require the judge of the court before which the conviction was had, or the district attorney by whom the action was prosecuted, to furnish the Governor or the board, without delay, with a summarized statement of the facts proved on the trial, and of any other facts having reference to the propriety of granting or refusing said application, together with his or her recommendation for or against the granting of the same and his or her reason for such recommendation.