Tenn. R. Civ. P. 28.02
In a foreign country, depositions may be taken (1) on notice before a person authorized to administer oaths in the place in which the examination is held, either by the law thereof or by the law of the United States, or (2) before a person commissioned by the court, and a person so commissioned shall have the power by virtue of the commission to administer any necessary oath and take testimony, or (3) pursuant to a letter rogatory. A commission or a letter rogatory shall be issued on application and notice and on terms that are just and appropriate. It is not requisite to the issuance of a commission or a letter rogatory that the taking of the deposition in any other manner is impracticable or inconvenient; and both a commission and a letter rogatory may be issued in proper cases. A notice or commission may designate the person before whom the deposition is to be taken either by name or descriptive title. A letter rogatory may be addressed "To the Appropriate Authority in (here name the country)."Evidence obtained in response to a letter rogatory need not be excluded merely for the reason that it is not a verbatim transcript or that the testimony was not taken under oath or for any similar departure from the requirements for depositions taken within the United States under these rules.
Tenn. R. Civ. P. 28.02