If a minor is found to be a person described in Section 601 or 602 and the court does not remove the minor from the physical custody of his or her parent or guardian, the court, as a condition of probation, may require the minor to submit to urine testing upon the request of a peace officer or probation officer for the purpose of determining the presence of alcohol or drugs.
Ca. Welf. and Inst. Code § 729.3