statutory(1. of or relating to formal laws or statutes: statutory acts 2. controlled or determined by a law or rule: He had reached the statutory age of retirement. [=the age at which retirement was required by law]. MWALD Alexander Demidov)
treaty rights(In Australia, Canada, New Zealand and the United States the term treaty rights specifically refers to rights for indigenous peoples enumerated in treaties with settler societies that arose from European colonization. wikipedia.org'More)