Ala. Code § 45-20-71.24: Contracts, Deeds, and Conveyances.

Any contract, deed, or conveyance signed by the president of the board, and witnessed by the clerk of the board, on orders of and at the direction of the board, shall be valid and binding obligations of the county. Provided, further, that the president pro tempore may sign in lieu of the president in the absence of such president.