Cal. Welf. & Inst. Code § 3200

(a) If at any time the Director of Corrections is of the opinion that a person committed pursuant to Article 3 (commencing with Section 3100) while in outpatient status has abstained from the use of narcotics, other than as medically prescribed in a narcotic treatment program pursuant to Section 3154, for at least six consecutive months and has otherwise complied with the conditions of his or her release, the director shall recommend to the Narcotic Addict Evaluation Authority that the person be discharged from the program. If the authority concurs in the opinion of the director, it shall discharge the person from the program.

(b) If at any time the director is of the opinion that a person committed for a period of 24 months, or less, pursuant to Article 2 (commencing with Section 3050) while in outpatient status has abstained from the use of narcotics, other than as medically prescribed in a narcotic treatment program pursuant to Section 3154, for at least 12 consecutive months and has otherwise complied with the conditions of his or her release, or if at any time the director is of the opinion that a person committed for a period of more than 24 months pursuant to Article 2 (commencing with Section 3050) while in outpatient status has abstained from the use of narcotics, other than as medically prescribed in a narcotic treatment program pursuant to Section 3154, for at least 16 consecutive months and has otherwise complied with the conditions of his or her release, the director shall so advise the Narcotic Addict Evaluation Authority. If the authority concurs in the opinion of the director, it shall file with the superior court of the county in which the person was committed a certificate alleging those facts and recommending to the court the discharge of the person from the program. The authority shall serve a copy of the certificate upon the district attorney of the county. Upon the filing of the certificate, the court shall discharge the person from the program. The court may, unless otherwise prohibited by law, modify the sentence, dismiss the criminal charges of which the person was convicted, or suspend further proceedings, as it deems warranted in the interests of justice. Where the person was certified to the superior court pursuant to Section 3050 the person shall be returned to the court that certified the person, which may dismiss the original charges. In any case where the criminal charges are not dismissed and the person is sentenced thereon, time served in custody while under commitment pursuant to Article 2 (commencing with Section 3050) shall be credited on the sentence. The dismissal shall have the same force and effect as a dismissal under Section 1203.4 of the Penal Code, except the conviction is a prior conviction for purposes of Division 10 (commencing with Section 11000) of the Health and Safety Code.