A member of a reserve force shall not carry a weapon in the line of duty until the member has been approved by the governing body and certified by the Iowa law enforcement academy council to carry weapons. After approval and certification, a reserve peace officer may carry a weapon in the line of duty only when authorized by the chief of police, sheriff, commissioner of public safety or the commissioner’s designee, or director of the judicial district department of correctional services or the director’s designee, as the case may be.