An attestation clause is a provision at the end of an instrument, especially a will, that is signed by witnesses and recites the formalities required to make the instrument effective. A formal attestation clause itself can serve as prima facie evidence of the facts within the instrument. An attestator operates as a witness to confirm how a document was executed. In the context of wills, attestation clauses are customary but, unlike the signatures of attesting witnesses, not necessary to the valid execution of the will. Nonetheless, it serves the purpose of creating a (rebuttable) presumption of the will's execution by confirming that, for example, the statutory requirements of the will have been met and that the signatures are genuine.
New York courts have held that attestation clauses are effective even if the attesting witnesses lack recollection of the details to the will or are deceased. However, impeaching evidence may be used to challenge the validity of an attestation clause. For example, where it can be shown that the witnesses signed an attestation clause citing details that were contrary to the actual situation, or that the witnesses did not read the clause before signing, the presumption of proper execution created by the attestation clause will be destroyed .
[Last updated in December of 2021 by the Wex Definitions Team]