Colo. Rev. Stat. § 11-24-102
Any bank or trust company qualified to act as fiduciary in this state may establish and operate, alone or jointly with another bank or trust company qualified to act as fiduciary in this state, common trust funds for the purpose of furnishing investments to itself as fiduciary, to itself and others as cofiduciaries, to other banks or trust companies as fiduciaries, or to other banks or trust companies and others as cofiduciaries. Such fiduciary or cofiduciary may invest funds which it lawfully holds for investment in interests in such common trust funds, if such investment is not prohibited by the instrument, judgment, decree, or order creating such fiduciary relationship, and if, in the case of cofiduciaries, the bank or trust company procures the consent of its cofiduciaries to such investment. Any person acting as cofiduciary with any such bank or trust company is hereby authorized to consent to the investment in such interests. In determining whether the investment of funds received or held by a bank or trust company as fiduciary in a common trust fund is proper, the bank or trust company may consider the common fund as a whole and shall not be prohibited from making such investment because of any particular asset.
C.R.S. § 11-24-102