Cal. Penal Code § 1203.45

(a) When a person was under 18 years of age at the time of commission of a misdemeanor and is eligible for, or has previously received, the relief provided by Section 1203.4 or 1203.4a, that person, in a proceeding under Section 1203.4 or 1203.4a, or a separate proceeding, may petition the court for an order sealing the record of conviction and other official records in the case, including records of arrests resulting in the criminal proceeding and records relating to other offenses charged in the accusatory pleading, whether the defendant was acquitted or charges were dismissed. If the court finds that the person was under 18 years of age at the time of the commission of the misdemeanor, and is eligible for relief under Section 1203.4 or 1203.4a or has previously received that relief, it may issue its order granting the relief prayed for. Thereafter the conviction, arrest, or other proceeding shall be deemed not to have occurred, and the petitioner may answer accordingly any question relating to their occurrence.
(b) This section applies to convictions that occurred before, as well as those that occur after, the effective date of this section.
(c) This section shall not apply to offenses for which registration is required under Section 290, to violations of Division 10 (commencing with Section 11000) of the Health and Safety Code, or to misdemeanor violations of the Vehicle Code relating to operation of a vehicle or of a local ordinance relating to operation, standing, stopping, or parking of a motor vehicle.
(d) This section does not apply to a person convicted of more than one offense, whether the second or additional convictions occurred in the same action in which the conviction as to which relief is sought occurred or in another action, except in the following cases:
1. (1) One of the offenses includes the other or others.
2. (2) The other conviction or convictions were for the following:
  1. (A) Misdemeanor violations of Chapters 1 (commencing with Section 21000) to 9 (commencing with Section 22500), inclusive, Chapter 12 (commencing with Section 23100), or Chapter 13 (commencing with Section 23250) of Division 11 of the Vehicle Code, other than Section 23103, 23104, 23105, 23152, 23153, or 23220.
  2. (B) Violation of a local ordinance relating to the operation, stopping, standing, or parking of a motor vehicle.
3. (3) The other conviction or convictions consisted of any combination of paragraphs (1) and (2).
(e) This section shall apply in a case in which a person was under 21 years of age at the time of the commission of an offense as to which this section is made applicable if that offense was committed prior to March 7, 1973.
(f)
1. (1) A petition for relief under this section shall not be denied due to an unfulfilled order of restitution or restitution fine.
2. (2) An unfulfilled order of restitution or a restitution fine shall not be grounds for finding that a defendant did not fulfil the conditions of probation for the entire period of probation.
3. (3) When the court considers a petition for relief under this section, in its discretion and in the interest of justice, an unpaid order of restitution or restitution fine shall not be grounds for denial of the petition for relief.
(g) In an action or proceeding based upon defamation, a court, upon a showing of good cause, may order the records sealed under this section to be opened and admitted into 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.