Cal. Penal Code § 1203.4a

(a) Every defendant convicted of a misdemeanor and not granted probation, and every defendant convicted of an infraction shall, at any time after the lapse of one year from the date of pronouncement of judgment, if they have fully complied with and performed the sentence of the court, are not then serving a sentence for an offense and are not under charge of commission of a crime, and have, since the pronouncement of judgment, lived an honest and upright life and have conformed to and obeyed the laws of the land, be permitted by the court to withdraw their plea of guilty or nolo contendere and enter a plea of not guilty; or if they have been convicted after a plea of not guilty, the court shall set aside the verdict of guilty; and in either case the court shall dismiss the accusatory pleading against the defendant, who shall be released from all penalties and disabilities resulting from the offense of which they have been convicted, except as provided in Chapter 3 (commencing with Section 29900) of Division 9 of Title 4 of Part 6 of this code or Section 13555 of the Vehicle Code.
(b) If a defendant does not satisfy all the requirements of subdivision (a), after a lapse of one year from the date of pronouncement of judgment, a court, in its discretion and in the interest of justice, may grant the relief available pursuant to subdivision (a) to a defendant convicted of an infraction, or of a misdemeanor and not granted probation, or both, if the defendant has fully complied with and performed the sentence of the court, is not then serving a sentence for any offense, and is not under charge of commission of a crime.
(c)
1. (1) The defendant shall be informed of the provisions of this section, either orally or in writing, at the time they are sentenced. The defendant may make an application and change of plea in person or by attorney, or by the probation officer authorized in writing, provided that, in any subsequent prosecution of the defendant for any other offense, the prior conviction may be pleaded and proved and shall have the same effect as if relief had not been granted pursuant to this section.
2. (2) Dismissal of an accusatory pleading pursuant to this section does not permit a person to own, possess, or have in their custody or control a firearm or prevent their conviction under Chapter 2 (commencing with Section 29800) of Division 9 of Title 4 of Part 6.
3. (3) Dismissal of an accusatory pleading underlying a conviction pursuant to this section does not permit a person prohibited from holding public office as a result of that conviction to hold public office.
4. (4) Dismissal of an accusation or information pursuant to this section does not release the defendant from the terms and conditions of an unexpired criminal protective order that has been issued by the court pursuant to paragraph (1) of subdivision (i) of Section 136.2, subdivision (j) of Section 273.5, subdivision (l) of Section 368, or subdivision (k) of Section 646.9. These protective orders shall remain in full effect until expiration or until any further order by the court modifying or terminating the order, despite the dismissal of the underlying accusation or information.
(d) This section applies to a conviction specified in subdivision (a) or (b) that occurred before, as well as those occurring after, the effective date of this section, except that this section does not apply to the following:
1. (1) A misdemeanor violation of subdivision (c) of Section 288.
2. (2) A misdemeanor falling within the provisions of Section 42002.1 of the Vehicle Code.
3. (3) An infraction falling within the provisions of Section 42001 of the Vehicle Code.
(e)
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 fully comply with and perform the sentence of the court or a finding that a defendant has not lived an honest and upright life and has not conformed to and obeyed the laws of the land.
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.
(f) A petition for dismissal of an infraction pursuant to this section shall be by written declaration, except upon a showing of compelling need. Dismissal of an infraction shall not be granted under this section unless the prosecuting attorney has been given at least 15 days’ notice of the petition for dismissal. It shall be presumed that the prosecuting attorney has received notice if proof of service is filed with the court.
(g) Any determination of amount made by a court under this section shall be valid only if either (1) made under procedures adopted by the Judicial Council or (2) approved by the Judicial Council.