If the names on the list from which certification is being made represent fewer than three ranks, then, consistent with board rules, additional eligibles may be certified from the various lists next lower in order of preference until names from three ranks appear. If there are fewer than three names available for certification, and the appointing authority does not choose to appoint from among these, the appointing authority may demand certification of three names. In that case, examinations shall be conducted until at least three names may be certified by the procedure described in this section, and the appointing authority shall fill the position by appointment of one of the persons certified.
Ca. Gov. Code § 19057.1