The avoidable consequences rule is a concept in United States jurisprudence which comes from a common-law rule barring recovery of damages that a tort victim "could have avoided by the use of reasonable effort or expenditure after the commission of the tort."[1] This concept recognizes as fact, that if a plaintiff is injured by a defendant, that the plaintiff must take reasonable steps to avoid aggravating the injuries caused by the defendant.
For example, if one thinks of a surgery as highly dangerous and likely to cause a greater likelihood of injury and damages, perhaps because the surgery itself is unreasonable, a plaintiff must take reasonable steps to avoid aggravating the injuries. Thus the duty to mitigate is exercised when a reasonable person declines risky surgery for fear that it may make the entire injury worse.
Religious beliefs may not be considered when determining whether a plaintiff with a duty to mitigate injuries, acted unreasonably when they failed to mitigate injuries on the grounds that it was against their religion.