Cal. Welf. & Inst. Code § 256.5

A juvenile hearing officer may request the juvenile court judge or referee to issue a warrant of arrest against a minor who is issued and signs a written notice to appear for any violation listed in Section 256 and who fails to appear at the time and place designated in the notice. The juvenile court judge or referee may issue and have delivered for execution a warrant of arrest against a minor within 20 days after the minor’s failure to appear as promised or within 20 days after the minor’s failure to appear after a lawfully granted continuance of his or her promise to appear. A juvenile hearing officer who is also a referee or juvenile court judge may personally issue the warrant of arrest.