According to the libertarian theorist David D. Friedman, "[m]edieval Icelandic institutions have several peculiar and interesting characteristics; they might almost have been invented by a mad economist to test the lengths to which market systems could supplant government in its most fundamental functions".Friedman, David D. (1979). "Private Creation and Enforcement of Law: A Historical Case". Retrieved 12 August 2005. While not directly labeling it anarcho-capitalist, Friedman argues that the legal system of the Icelandic Commonwealth comes close to being a real-world anarcho-capitalist legal system. Although noting that there was a single legal system, Friedman argues that enforcement of the law was entirely private and highly capitalist, providing some evidence of how such a society would function. Friedman further wrote that "[e]ven where the Icelandic legal system recognized an essentially 'public' offense, it dealt with it by giving some individual (in some cases chosen by lot from those affected) the right to pursue the case and collect the resulting fine, thus fitting it into an essentially private system".
