Colo. Rev. Stat. § 13-16-101 – Security for costs.

(1) In all actions on official bonds for the use of any persons, actions on the bonds of executors, administrators, or guardians, and qui tam actions on any penal statute, the person or plaintiff for whose use the action is to be commenced, before he or she institutes such suit, shall file or cause to be filed with the clerk of the court in which the action is to be commenced an instrument in writing as described in subsection (3) of this section for security for the payment of costs of suit.
(2) In all cases in law and equity where the plaintiff, or the person for whose use an action is to be commenced, is not a resident of this state, upon motion of the defendant or any officer of the court pursuant to section 13-16-102, the court may require the nonresident plaintiff to give an instrument in writing for the payment of costs of suit as described in subsection (3) of this section; except that, to ensure that access to the courts is not unreasonably denied, a court shall not require an instrument in writing for the payment of costs of suit in excess of five thousand dollars.
(3) As used in this section and section 13-16-102, instrument in writing means an instrument in writing of some responsible person, being a resident of this state, to be approved by the clerk, whereby such person shall acknowledge himself or herself bound to pay, or cause to be paid, all costs which may accrue in such action either to the opposite party or to any of the officers of such courts, which instrument may be in form as follows:
A. B. )
vs. ) .......... Court.
C. D. )
I do hereby enter myself security for costs in this case, and acknowledge myself bound to pay, or cause to be paid, all costs which may accrue in this action, either to the opposite party or to any of the officers of this court pursuant to the laws of this state.
..............................................................
Dated this ........ day of ........, 20.. .

Source: R.S. p. 153, § 1. G.L. § 323. G.S. § 397. R.S. 08: § 1064. C.L. § 6580. CSA: C. 43, § 10. CRS 53: § 33-1-1. C.R.S. 1963: § 33-1-1. L. 2009: Entire section amended, (HB 09-1305), ch. 311, p. 1690, § 1, effective September 1.