Article 134  Jurisdiction
The constitutional court decides:

Article 135  Composition
(1) The constitutional court consists of fifteen justices; one third being appointed by the president, one third by parliament in joint session, and one third by ordinary and administrative supreme courts.
(2) Justices are chosen from among magistrates including those in retirement, from among supreme ordinary and administrative courts, from among university full professors of law, and from among lawyers with at least twenty years of practice.
(3) Justices are appointed for nine years, their term beginning the day they are sworn in and with no re-appointment.
(4) At the end of this term justices have to leave office and may no longer exercise its functions.
(5) The court elects from among its members and according to rules established by law its president who shall remain in office for three years and may be re-elected, but not exceed the ordinary term of justices.
(6) The office of justice is incompatible with membership in parliament or in a regional council, with the exercise of the legal profession, or with any other position and office defined by law.
(7) When sitting to decide on a case of impeachment against the president, the court consists of sixteen additional members, who are drawn by lot from a list of citizens elected by parliament every nine years, from among those possessing the qualifications for election to the senate, by the same procedures as for the appointment of the ordinary justices.
 
Article 136  Unconstitutional Laws
(1) When the court declares a law or an act with the force of law unconstitutional, the norm ceases to have effect from the day following the publication of the decision.
(2) The decision of the court is published and reported to parliament and to the regional councils involved for them to take appropriate measures in constitutional forms where necessary.
 
Article 137  Conditions and Terms
(1) A constitutional law establishes the conditions, forms, and terms for challenging the constitutionality of a law and guarantees the independence of the justices.
(2) An ordinary law defines all other rules necessary for the establishment and functioning of the court.
(3) Decisions of the constitutional court may not be appealed.
 
 
Article 138  Procedure for Constitutional Amendment
(1) Law amending the constitution and other constitutional acts are adopted by each of the two chambers twice within no less than three months and need the approval of a majority of the members of each chamber in the second voting.
(2) Such laws are afterwards submitted to popular referendum when, within three months of their publication, a request is made by one fifth of the members of either chamber, by 500,000 electors, or by five regional councils.  The law submitted to referendum is not promulgated if it does not receive the majority of valid votes.
(3) No referendum may be held if the law has been approved by each chamber in the second vote with a majority of two thirds of its members.
 
Article 139  Limit to Constitutional Amendments
The republican form of the state may not be changed by way of constitutional amendment.