C.R.S. § 13-72-104

Before a grand jury at any term of court is sworn or affirmed, the court shall appoint a foreman of such jury and an alternate foreman to act in the absence of the foreman, and such foreman or alternate foreman has power to administer an oath or affirmation to any and all witnesses who may be required to testify before such jury. He shall also endorse upon every bill that may be presented to a grand jury the finding of such jury that the same is “a true bill” or “not a true bill”, as the case may be, and sign his name thereto before the same is returned into court.