D.C. Code § 23-1326

If it appears by affidavit that the testimony of a person is material in any criminal proceeding, and if it is shown that it may become impracticable to secure his presence by subpoena, a judicial officer shall impose conditions of release pursuant to section 23-1321 . No material witness shall be detained because of inability to comply with any condition of release if the testimony of such witness can adequately be secured by deposition, and further detention is not necessary to prevent a failure of justice. Release may be delayed for a reasonable period of time until the deposition of the witness can be taken pursuant to the Federal Rules of Criminal Procedure.