Q: Is a person liable for damage that he did unintentionally?

A: The Mishnah (B.K. 26a) teaches: “A person is always considered mu’ad (prone to do damage), whether accidental or intended, whether awake or asleep.” The Gemara (26b) adds that he is liable even for oness (uncontrollable actions) as for willing actions. Therefore, a person who was blown off a roof by an unusually strong gust of wind is liable if he caused damage (27a).

Some understand this rule literally, that a person is obligated even for circumstances beyond his control. This is the simple understanding of the Rambam (Hil. Chovel Umazik 6:1) and Shulchan Aruch (C.M. 378:1-2; Shach 378:1).

Tosafos (B.K. 27b), on the other hand, limits this rule to uncontrollable circumstances that contain an element of carelessness. However, a person is not liable for cases of oness when there is no element of fault. The Rema follows this opinion (378:1; 421:4).

Even according to the stringent view, a person is not liable for oness if the damaged party was negligent in leading to the damage (421:4) or if the incident was a great oness, totally beyond his control (378:3; Pischei Choshen, Nezikin 1:6-9).