Causation in the law

Abstract

Legal systems utilize causal concepts to attribute responsibility for harm, distinguishing between purely explanatory functions and the normative task of fixing liability. Determining a causal connection involves two primary stages: establishing “cause-in-fact” and defining “proximate cause” to limit the extent of responsibility. Factual causation is typically assessed through the “but-for” test, though complexities in cases of over-determination lead some theorists to favor the NESS (Necessary Element of a Sufficient Set) criterion or quantitative “substantial factor” models. Legal responsibility is not synonymous with causing harm; it is further constrained by the scope of the legal rule, the foreseeability of outcomes, and the potential intervention of superseding events. Causal minimalism posits that only factual relevance is strictly causal, while further limitations are matters of legal policy or risk distribution. Conversely, alternative frameworks suggest that limits on responsibility reflect ordinary or metaphysical causal judgments, such as whether a later intervention breaks the causal chain or whether the agency significantly increased the objective probability of the harm. These criteria function to navigate the distribution of social risks while maintaining a coherent link between individual agency and its impact on the world. – AI-generated abstract.