Assumption of risk is an affirmative defense which states that someone cannot be held liable when the injured party expressly entered into a situation knowing there was a possibility of harm. As an example, playing football is a physical game. When you step on to the field, you’re assuming the risks (and possibly consenting, too) of being tackled and physically contacted within the ordinary scope of the game.
There are two types of assumption of risk: express and implied. Express assumption of risk occurs when a plaintiff expressly agrees in advance that the defendant does not owe him/her a duty. Recovery is completely barred because there is no duty in the first place. Very often, therefore, individuals will try to have releases signed in advance in an attempt to eschew a duty. Such releases/contracts are disfavored in Missouri, but can be enforceable in certain circumstances; it depends on the case and language of the release/contract. See Alack v. Vic Tanny International of Missouri, Inc., 923 S.W.2d 330, 334 (Mo. 1996).
Implied assumption of risk is divided into two further categories: implied primary and implied secondary. Implied primary assumption of risk turns on if the defendant had a duty to protect the plaintiff from a risk of harm. This typically occurs where the parties have freely and voluntarily entered a relationship in which the plaintiff knows of the risks involved. The plaintiff’s consent is implied from the act of electing to participate. Implied secondary is when the defendant owes a duty of care but the plaintiff knowingly proceeds to encounter a known risk imposed by the breach of duty. See Lewis v. Snow Creek, 6 S.W.388 (Mo. Ct. App. 2000).