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In a claim in Negligence, it is always necessary for the claimant to show the he was owed aduty of care by the defendant, that the defendant was in breach of that duty, and the the breach caused the claimant's loss or injury. On those terms, a person who is injured whilst trying to rescue or assist a victim of another's negligence will find it difficult to succeed. The first problem the rescuer might face is that his presence at the site of the accident might not be reasonably forseeable, and this would generally be fatal to a claim. The second problem, assuming he can overcome the first, is that he may have difficulty showing that the defendant's negligence is the cause of his own injuries. A third problem is that the defendant can argue that volenti non fit injuria applies, that is, the rescuer is acting of his own volition, and therefore has accepted the risks.

As a matter of policy, these difficulties are usually set aside by the courts, as to do otherwise would be to discourage public-spiritedness. It is deemed to be reasonably forseeable that if one's carelessness creates a dangerous situation, someone may need to be rescued. It is also assumed that a rescuer is not volenti, as rescue is a duty, not a freely-chosen act. Moreover, and partly following from these assumptions, a negligent defendant can be liable to a rescuer even in circumstances where he would not be liable to a primary victim.

However, in modern law rescuers are not in a more 'privileged' position than ordinary bystanders. It had been thought that rescuers who experiencedpsychiatric injury could succeed in a claim in circumstances where psychiatric injury was not reasonably forseeable, unlike bystanders. But, according to white v ccsouth yorkshire police (1998), this is not so: the tests in alcock v ccsouth yorkshire police (1991) apply to rescuer to the same extent as to bystanders.