Cal. MVC § 1219

Whenever the bonds of a district have been investigated and certified by any officer of this state authorized to make such investigation and certification, and by the authority of such certification have been declared to be legal for investment by savings banks of this state, then such bonds may be lawfully purchased or received in pledge for loans by savings banks, building and loan associations, trust companies, insurance companies, guardians, conservators, executors, administrators, special administrators, or by any public officer within this state holding funds which by law may be invested or loaned.