It is unlawful for any person liable to tax under this chapter to fail or refuse to make a return, or to pay the tax or installment thereof when due, or for any person to make any false or fraudulent return or petition, or any false statement or representation in, or in connection with, any such return or petition, or to aid or abet another in any attempt to evade payment of the tax, or any part thereof, or for any person to fail to appear and/or testify in response to subpoena issued pursuant to this chapter, or to testify falsely upon an investigation of the correctness of a return, or upon the hearing of an appeal, or in any manner to hinder or delay the city or any of its officers or auditors in carrying out the provisions of this chapter. (Ord. 814 § 22, 1976).