In Colorado, as in most legal jurisdictions, the burden of proof in a dispute typically lies with the plaintiff. This means that in an HOA dispute, the individual or party bringing the action (the plaintiff) must prove their case and allegations against the defendant. The plaintiff is responsible for providing evidence that substantiates their claims to meet the required standard of proof, which in civil cases like these is usually "preponderance of the evidence." This standard requires showing that something is more likely to be true than not.

An affirmative defense, on the other hand, is a set of facts or legal arguments that a defendant can raise to defeat the plaintiff’s claim, even if the claim is factually true. In Colorado, a statute can indeed be cited as an affirmative defense by the defendant. If the defendant successfully proves the affirmative defense, it can entirely negate or mitigate the legal consequences of the alleged facts, even if those facts are proven by the plaintiff.

For example, if a homeowner is in a dispute with their HOA and the HOA's actions are governed or permitted by a specific statute, the homeowner (as the defendant, if the HOA sues) could use that statute as an affirmative defense, arguing that their actions or the situation complies with the statutory requirements or exceptions.

In summary, in Colorado HOA disputes, the plaintiff carries the burden of proof to establish their claims, while the defendant can use statutes as part of an affirmative defense to challenge or nullify the plaintiff’s allegations.