Sociopolitical organization is complicated by the presence of sometimes conflicting forms of land tenure and systems introduced at different times by the Spaniards and Mexicans that crosscut traditional organization.
There are two forms of communal land tenure present in the region:
-The comunidad is an older, indigenous form, in which land is held partilineally and inherited by sons or widows. Comunidades are governed by a popularly elected asamblea (assembly of voting members), who decide upon matters presented and selects minor political and economic officials.
-The ejido is a form of communal land-tenure system provided for in the constitution of 1917, following the Mexican Revolution. It allocated communal lands to applicants—whether Indian, mestizo, or together—to be held as long as the land is used economically.
Under the ejidal system, land is not officially or legally inheritable, but actual practice often violates this proviso. An elected body of officials governs the ejido and its economic business. Residential units found within ejidos and comunidades include towns and rancherías.
The ejidal officers, controls the land-tenure system. A comisario is elected for a three-year term to transact business and deal with officials of the Secretaría de la Reforma Agraria, the federal agency that oversees and adjudicates matters regarding ejidos.