Conformed as unicameral assemblies, they are composed of deputies elected under the principles of relative majority and by proportional representation, in accordance with the specific regulations of local laws, but following the general bases of the federal constitution.Its members are elected by universal vote under the two principles already mentioned; the former directly and the others according to the multi-member list system established by federal law.The term of office is three years with the option of immediate reelection, as long as it is representing the party or coalition that originally nominated the deputy.For each titular deputy, an alternate is elected; This being the one who will make up for the temporary or permanent absences of his running mate.Its characteristics and general bases are supported by section II of article 116 of the Political Constitution of the United Mexican States.