Cal. Penal Code § 851.7

(a) Any person who has been cited or arrested for a misdemeanor or felony, with or without a warrant, while a minor, may, during or after minority, petition the court in which the proceedings occurred or, if there were no court proceedings, the court in whose jurisdiction the citation or arrest occurred, for an order sealing the records in the case, including any records of citation, arrest, and detention, if any of the following occurred:
1. (1) The person was released pursuant to paragraph (1) of subdivision (b) of Section 849.
2. (2) Proceedings against the person were dismissed, or the person was discharged, without a conviction or adjudication.
3. (3) The person was acquitted.
(b) If the court finds that the petitioner is eligible for relief under subdivision (a), it shall issue its order granting the relief prayed for. Thereafter, the citation, arrest, detention, and any further proceedings in the case shall be deemed not to have occurred, and the petitioner may answer accordingly any question relating to their occurrence.
(c) This section applies to arrests and any further proceedings that occurred before, as well as those that occur after, the effective date of this section.
(d) This section does not apply to any person taken into custody pursuant to Section 625 of the Welfare and Institutions Code, or to any case within the scope of Section 781 of the Welfare and Institutions Code, unless, after a finding of unfitness for the juvenile court or otherwise, there were criminal proceedings in the case, not culminating in conviction. If there were criminal proceedings not culminating in conviction, this section shall be applicable to the criminal proceedings if the proceedings are otherwise within the scope of this section.
(e) This section does not apply to arrests for, and any further proceedings relating to, any of the following:
1. (1) Offenses for which registration is required under Section 290.
2. (2) Offenses under Division 10 (commencing with Section 11000) of the Health and Safety Code.
3. (3) Offenses under the Vehicle Code or any local ordinance relating to the operation, stopping, standing, or parking of a vehicle.
(f) In any action or proceeding based upon defamation, a court, upon a showing of good cause, may order any records sealed under this section to be opened and admitted in evidence. The records shall be confidential and shall be available for inspection only by the court, jury, parties, counsel for the parties, and any other person who is authorized by the court to inspect them. Upon the judgment in the action or proceeding becoming final, the court shall order the records sealed.
(g)
1. (1) A record that has been sealed pursuant to this section may be accessed, inspected, or utilized by the prosecuting attorney in order to meet a statutory or constitutional obligation to disclose favorable or exculpatory evidence to a defendant in a criminal case in which the prosecuting attorney has reason to believe that access to the record is necessary to meet the disclosure obligation. A request to access information in the sealed record for this purpose, including the prosecutor’s rationale for believing that access to the information in the record may be necessary to meet the disclosure obligation and the date by which the records are needed, shall be submitted by the prosecuting attorney to the juvenile court. The juvenile court shall review the case file and records that have been referenced by the prosecutor as necessary to meet the disclosure obligation and any response submitted by the person having the sealed record. The court shall approve the prosecutor’s request to the extent that the court has, upon review of the relevant records, determined that access to a specific sealed record or portion of a sealed record is necessary to enable the prosecuting attorney to comply with the disclosure obligation. If the juvenile court approves the prosecuting attorney’s request, the court shall state on the record appropriate limits on the access, inspection, and utilization of the sealed record information in order to protect the confidentiality of the person whose sealed record is accessed pursuant to this subdivision. A ruling allowing disclosure of information pursuant to this subdivision does not affect whether the information is admissible in a criminal or juvenile proceeding. This subdivision does not impose any discovery obligations on a prosecuting attorney that do not already exist.
2. (2) This subdivision does not apply to juvenile case files pertaining to matters within the jurisdiction of the juvenile court pursuant to Section 300 of the Welfare and Institutions Code.
(h) This section applies in any case in which a person was under 21 years of age at the time of the commission of an offense to which this section applies if that offense was committed prior to March 7, 1973.