North Carolina General Statutes Chapter 15A. Criminal Procedure Act § 15A-823. Securing attendance of prisoner in federal institution as witness in proceeding in the State

(1) A criminal proceeding is pending in a court of this State; and

(2) There is reasonable cause to believe that a person confined in a federal prison or other federal custody, either within or outside this State, possesses information material to such criminal proceeding; and

(3) His attendance as a witness in such action or proceeding is desired by a party thereto, the court may issue a certificate, known as a writ of habeas corpus ad testificandum, addressed to the Attorney General of the United States certifying all such facts and requesting the Attorney General of the United States to cause the attendance of such person as a witness in such court for a specified number of days under custody of a federal public servant.