The crime of assault varies from state to state (and under federal law), but is generally defined as intentionally putting another person in reasonable apprehension or fear of an imminent (immediate) harmful or offensive contact. The crime of assault may be committed even if there is no physical contact, as the criminal physical contact constitutes the separate crime of battery. In many states assaulting a police officer or peace officer who is performing official duties (such as making a lawful arrest) is a more serious offense—sometimes a felony.
In Colorado, assault is defined under state statutes and is categorized into three degrees. First-degree assault (C.R.S. 18-3-202) is the most serious, involving the intentional causing of serious bodily injury, often with a deadly weapon, and is a class 3 felony. Second-degree assault (C.R.S. 18-3-203) involves intentionally causing bodily injury to another person with a weapon, or causing injury while preventing a peace officer or firefighter from performing their duties, and is a class 4 felony. Third-degree assault (C.R.S. 18-3-204) is knowingly or recklessly causing bodily injury to another person, or with criminal negligence causing bodily injury with a deadly weapon, and is a class 1 misdemeanor. Assaulting a police officer or peace officer is indeed considered a more serious offense in Colorado and can lead to enhanced penalties, including longer prison terms and higher fines.