C.R.S. § 16-9-301
16-9-301. Definitions
16-9-301. Definitions. As used in this part 3, unless the context otherwise requires:
(1) "Summons" includes a subpoena, order, or other notice requiring the appearance of a witness.
(2) "Witness" includes a person whose testimony is desired or who is desired to produce tangible evidence in any proceeding or investigation by a grand jury or a criminal action or proceeding in this state.