The one of the most mysterious and badly studied norms of a common law in the Northeast Caucasus remains the Ishkil. It for a long time draws attention of scientists. But nobody went further the general statement of a question and at all has not given the detailed description of this custom. The researcher's mainly studied the social maintenance and an origin of the Ishkil instead of its legal forms during an epoch of Russian gain from the 18^th till first half of the 19^th century from which the majority of sources about the Ishkil has reached.