C.R.S. § 18-12-114

(1) Firearms must be responsibly and securely stored when they are not in use to prevent access by unsupervised juveniles and other unauthorized users. A person responsibly and securely stores a firearm when:

(a) The person carries the firearm on his or her person or within such close proximity thereto that the person can readily retrieve and use the firearm as if the person carried the firearm on his or her person;

(b) The firearm is kept in a locked gun safe or other secure container or in a manner that a reasonable person would believe to be secure and a juvenile or resident of the premises who is ineligible to possess a firearm does not have access to the key, combination, or other unlocking mechanism necessary to open the safe or container;

(c) The person properly installs a locking device on the firearm and a juvenile or resident of the premises who is ineligible to possess a firearm does not have access to the key, combination, or other unlocking mechanism necessary to remove the locking device; or

(d) The firearm is a personalized firearm and the safety characteristics of the firearm are activated.

(2) (a) A person commits unlawful storage of a firearm when the person fails to responsibly and securely store a firearm, as described in subsection (1) of this section, upon any premises that the person owns or controls and the person knows or reasonably should know that:

(I) A juvenile can gain access to the firearm without the permission of the juvenile's parent or guardian; or

(II) A resident of the premises is ineligible to possess a firearm pursuant to state or federal law.

(b) Unlawful storage of a firearm is a class 2 misdemeanor.

(c) It is an affirmative defense to the offense of unlawful storage of a firearm that a juvenile gained possession of, and used, the firearm for the purpose of exercising the rights contained in section 18-1-704 or 18-1-704.5 or in defense of livestock.

(3) This section does not apply to storing an antique firearm, as defined in 18 U.S.C. sec. 921 (a)(16), as amended, or a curio or relic, as defined in 27 CFR 478.11, as amended.