The article discusses the issue of liability for acting in the delusive self-defence, which takes place when a perpetrator commits a prohibited act in an erroneous belief that he exercises the features of the right of self-defence. Due to the fact that a perpetrator is in a special situation, the Criminal Code treats this error as a circumstance excluding guilt, provided that the error is justified; and in case it is unjustified, taking into consideration special circumstances in which a perpetrator has been, a court may apply extraordinary mitigation of punishment.