2 (a) That's right. Even if a defendant's conduct has created the situation in which the harm occurred, a court may decide that a later event, such as another person's free and deliberate act, has intervened as the legal cause of the harm. A court considers an event as 'intervening' when it was sufficient to break the causal link between the defendant's conduct and the eventual harm. In such cases, the defendant is not liable because the harm is no longer causally linked to the defendant's negligent conduct. Many factors are taken into account to decide whether an event is truly an intervening one, and it is difficult to state precise and accurate rules.
The following cases can be distinguished. They are not examples of a novus actus interveniens because the sequence of events that occurred was exactly what could be expected to happen.