According to Article 68 under the Constitution, no one can, at the same time, be Deputy and Senator, and the quality of Deputy or Senator is incompatible with the exercise of any public function of authority, except that of member of the Government. The Constitution also provides that other incompatibilities be established by organic law. The member of Parliament who finds himself or herself in one of the cases of incompatibility is bound to resign, the Deputy within 10 days, and the Senator within 30 days. The term of 10 days flows after the day when the case of incompatibility was found, and that of 30 days, after the day of the validation of the mandate, or after the day of appearance of the incompatibility. After expiry of these terms, the parliamentarian who is in one of these cases of incompatibility is declared or considered resigned, as the case may be.
The vacant seat will be taken by the immediately following candidate on the list of the party or political formation for which he or she stood. According to the Senate's Standing Orders, from the list are excluded people who no longer belong to the respective party or political formation. The Standing Orders of the Chamber of Deputies provides in this sense that up to the validation of the substitute's mandate, the party or political formation for which he or she stood must acknowledge in writing his or her affiliation to the respective party or political formation.
Changes occurring in a parliamentarian's activity during the exercise of his or her mandate are notified to the Standing Bureau within 10 days after the day of their appearance.