which causes a blunt-force injury. This is also known as the "extraordinary in hindsight" rule. A "threefold test" of foreseeability of damage, proximity of relationship and reasonableness was established in the case of Caparo v Dickman (1990) and adopted in the litigation between Lungowe and others and Vedanta Resources plc (Supreme Court ruling 2019). Direct causation Direct causation is a minority test, which addresses only the metaphysical concept of causation. It does not matter how foreseeable the result as long as what the negligent party's physical activity can be tied to what actually happened. The main thrust of direct causation is that there are no intervening causes between an act and the resulting harm. An intervening cause has several requirements: it must 1) be independent of the original act, 2) be a voluntary human act or an abnormal natural event, and 3) occur in time between the original act and the harm. Direct causation is the only theory that addresses only causation and does not take into account the culpability of the original actor. Risk enhancement/causal link The plaintiff must demonstrate that the defendant's action increased the risk that the particular harm suffered by the plaintiff would occur. If the action were repeated, the likelihood of the harm would correspondingly increase. This is also called foreseeable risk. Harm within the risk The harm within the risk (HWR) test determines whether the victim was among the class of persons who could foreseeably be harmed, and whether the harm was foreseeable within the class of risks. It is the strictest test of causation, made famous by Benjamin Cardozo in Palsgraf v. Long Island Railroad Co. case under New York state law. The first element of the test is met if the injured person was a member of a class of people who could be expected to be put at risk of injury by the action. For example, a pedestrian, as an expected user of sidewalks, is among the class of people put at risk by driving on a sidewalk, whereas a driver who is distracted by another driver driving on the sidewalk, and consequently crashes into a utility pole, is not. The HWR test is no longer much used, outside of New York law. When it is used, it is used to consider the class of people injured, not the type of harm. The main criticism of this test is that it