Aberratio ictus is a Latin term that refers to the accidental harm that occurs to someone when a criminal act is misdirected against him or her when he or she was otherwise an innocent bystander in the course of the crime. The term is used in criminal law cases as the transferred intent rule, which states that, even though the intended victim in a criminal act was not directly harmed, the actual victim who was harmed is assumed for legal purposes to be the intended victim. Other ways of referring to the Aberratio ictus principle include as mistake in the blow or false going of the blow. Legal precedents for accidental harm allow for full liability to be extended to the perpetrator of the act even though he or she missed his or her target in trying to cause injury to another.
In criminal cases where there is a mistake in the act object during the course of the crime, Aberratio ictus incidents become what is termed complex crimes. This is due to the fact that at least three parties are involved in Aberratio ictus crimes — the perpetrator, the intended victim, and the actual victim. Courts must evaluate guilt based on extenuating factors in such cases, such as the identity of the intended victim. Criminal liability will vary if the perpetrator's intended victim was randomly chosen instead of being a specifically targeted individual.
The nature of complex crimes also involves the fact that several felony charges can be brought against the perpetrator. Charges must take into account both the perpetrator's intended act, as well as the result of these intentions, which can include harm that was, in fact, caused to both the intended victim in a more minor way, as well as serious harm caused to any and all bystanders. An example in criminal law would be where a perpetrator designated as “A”, intended to kill a victim “B,” but, while attacking B, actually killed “C”. The perpetrator must be tried by the court for both his or her attack on B as well as his or her murder of C. Such cases often have complex crime designations that on the surface may not appear to make sense, like “homicide with attempted homicide.”
National approaches to Aberratio ictus also vary from country to country. In UK legal precedents, a false going or accidental murder is subject to the same penalty whether the victim was selected, completely unknown to the killer, or a case of mistaken identity. UK legal definitions define this as general malice or an immaterial mistake that does not mitigate the penalty for the crime. In other nations such as South Africa, Aberratio ictus is defined differently as an error in object, or dolus indeterminatus, and may have different penalties ascribed to it.
Since Aberratio ictus is a general legal principle, it also has applications outside of cases of bodily harm. Where the rules governing such crimes are more likely to differ from nation to nation are in situations like these. The concept of accidental harm can be attributed to any form of property damage for instance, from crimes such as arson, to looting or robbery.