This article introduces a significant yet largely overlooked problem in the law of torts: causal underdetermination. This problem occurs when the causal inquiry of a but-for test produces not one but two results, which are contradictory. According to the first, the negligent defendant is the likely cause of the plaintiff's injury, whereas according to the second, she is not. The article explains why causal underdetermination has escaped the radar of tort scholars and is perceived by courts as lack of causation. It demonstrates that the current practice in cases of causal underdetermination might lead to erroneous decisions, absolving negligent defendants of tort liability even when the evidence suggests that they are in fact the likely cause of the plaintiff's injury. This, in turn, the article asserts, may not only lead to underdeterrence among potential defendants, but also encourage manipulative litigation strategy to escape liability in retrospect. The article then proposes solutions that contend with causal underdetermination and resolve the difficulties that the current practice entails.

中文翻译：

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多重合理行为案例：侵权法中的因果关系不明确问题

本文介绍了侵权法中一个重要但在很大程度上被忽视的问题：因果关系不足。当一个but-for检验的因果查询产生的结果不是一个而是两个时，就会出现这个问题，这两个结果是相互矛盾的。根据第一个，疏忽的被告是原告受伤的可能原因，而根据第二个，她不是。这篇文章解释了为什么因果关系不足已经逃过了侵权学者的关注，并被法院视为缺乏因果关系。它表明，在因果关系不充分的情况下，当前的做法可能会导致错误的决定，即使有证据表明疏忽的被告实际上是原告受伤的可能原因，也可以免除侵权责任。反过来，这篇文章断言，不仅可能导致潜在被告的威慑力不足，而且还鼓励操纵诉讼策略以逃避责任。然后，本文提出了应对因果不确定性并解决当前实践带来的困难的解决方案。