(a) Except as provided in subdivision (b), the assessor may destroy any document when six years have elapsed since the lien date for the tax year for which that document was obtained. Documents may be destroyed when three years have elapsed since the lien date described in the preceding sentence, if the documents have been microfilmed, microfiched, imaged, or otherwise preserved on a medium that provides access to the documents. (b) Affidavits claiming an exemption, for the first time, pursuant to Sections 254.5, 257, and 277 may be destroyed by the assessor as follows: (1) Six years after the lien date of the tax year for which the exemption was last granted. (2) Three years after the lien date described in paragraph (1) if the documents have been microfilmed, microfiched, imaged, or otherwise preserved on a medium that provides access to the documents.
