Tennessee Code Title 40. Criminal Procedure § 40-17-107

(a) The clerk of the court in which a criminal cause is pending shall issue subpoenas, at any time, to any part of the state, for witnesses as either the district attorney general or the defendant may require.

(b) The clerk shall also issue a subpoena, without any application, for witnesses whose names are marked as witnesses by the district attorney general upon the indictment.

(c) The clerk shall issue no subpoena for a witness, on behalf of the state, except witnesses as are so marked or subsequently directed by the district attorney general, in writing, to be summoned.

(d) This section shall govern when a clerk is required to issue a subpoena in a criminal case in general sessions court. If any local rule of court conflicts with this section, this section shall prevail and the clerk shall issue subpoenas in accordance with this section.