C.R.S. § 18-8-102

(1) A person commits obstructing government operations if he intentionally obstructs, impairs, or hinders the performance of a governmental function by a public servant, by using or threatening to use violence, force, or physical interference or obstacle. (2) It shall be an affirmative defense that: (a) The obstruction, impairment, or hindrance was of unlawful action by a public servant; or (b) The obstruction, impairment, or hindrance was of the making of an arrest; or (c) The obstruction, impairment, or hindrance of a governmental function was by lawful activities in connection with a labor dispute with the government. (3) Obstructing government operations is a class 2 misdemeanor.