Colo. Rev. Stat. § 10-4-103
No voluntary partial payment of a claim against any person based on alleged liability of that person for injury or property damage arising out of any occurrence shall be construed as an admission of fault or liability, or as a waiver or release of claim, by the person receiving such payment. Such payment, moreover, shall not be admissible in any action, as evidence, for the purpose of determining the amount of any judgment with respect to the same parties as to such occurrence. Upon settlement of the claim, the parties may make any agreement they so desire in respect to all such voluntary partial payments. After entry of judgment, any such payment shall be treated as a credit against the judgment and is deductible from the amount of the judgment. If, after partial voluntary payments are made as provided for in this section, it is determined by final judgment of a court of competent jurisdiction that the payer is liable for an amount less than the voluntary payments already made, the payer shall have no right of action for the recovery of amounts by which the voluntary payments exceed the final judgment. No voluntary partial payments shall be construed to reduce the amount of damages which may be pleaded and proved in a court proceeding between the parties.
C.R.S. § 10-4-103