Tennessee Code Title 2. Elections § 2-17-109

(a) Poll books, voter signature lists and ballot applications, or copies of them, certified by the officer having custody of them, are official records and shall be received as evidence in any case arising out of the election. They may be impeached by other evidence.

(b) If the poll books, voter signature lists and ballot applications or copies of them are not certified, they may nonetheless be proved by other credible evidence and received as evidence in an election contest.