The organization of the Italian Republic is both the subject of the second part of the Constitution (from art. 55 onwards), which has been variously modified since its approval (the widest ranging reform was introduced by Const. Law 3/2001, which redefined the relations between State, Regions and Local Authorities.), and of several constitutional laws. The latter include Const. Laws 1/1948 and 1/1953 (both regulating the Constitutional Court) and the Statutes of the five Special Regions. All electoral legislation is on the other hand covered by non-constitutional laws.

The Italian constitutional system aims to provide a system of checks and balances between the various powers of the State rather than on a rigid division of them.

The Parliament is composed of the Chamber of Deputies and the Senate of the Republic, which have the same functions and equal powers. The Constitution adopted a model of an equal and perfect bicameralism in which the difference between the two Houses lies in how their members are elected rather than in their functions. Beyond the differences in their electoral systems, which are necessary to respect the constitutional principle according to which the Senate is elected on a regional basis, other differences include age requirements for the active and passive electorate and the number seats in the respective Houses: 630 for the Chamber of Deputies and 315 (plus a number of appointed life senators and ex-Presidents of the Republic) for the Senate.

The legislative function is performed collectively by the two Houses (art. 70): consequently, in order to become law, an identical text of each bill must be approved in both Houses of Parliament. Constitutional bills require double approval by each House and an absolute majority vote in the second round of voting.

With the exception of certain bills, including constitutional and budget bills, all bills may be subject to total or partial abrogation  by popular referendum if 500,000 voters or more request it . Similarly if 50,000 citizens sign their names in support of a draft bill, they may presente it to the Parliament.

The President of the Republic represents national unity. He is elected by Parliament with the two Houses sitting in joint session, together with the delegates from all the Italian regions. His term of office lasts seven years (arts. 83-85).

Several of the President’s powers have a direct effect on Parliament. The Head of State can call elections, dissolve the two Houses after consulting their Presidents; promulgate the bills approved by Parliament, which become law only after he has signed them, and can send them back to the Houses instead of promulgating them, requesting (only once) that they should be re-examined and he may make formal communications to the two Houses.

The President of the Republic is the commander of the Armed Forces and chairs the Superior Judicial Council. He nominates the President of the Council of Ministers (Prime Minister) and, after consulting the latter, the ministers, who form the Government (art. 92).

After nomination by the Head of State, the Government must obtain the confidence of each of the two Houses, before which it must appear no later than ten days after its formation in order to illustrate its programme; at the conclusion of the debate, the Houses vote on a motion of confidence by roll call (art. 94).

The confidence relation may be challenged by presenting a no confidence motion in the Chamber of Deputies or the Senate. The Government itself may formally request the verification of the majority supporting it by raising the question of confidence in the case of the approval (or rejection) of proposals deemed essential to its action. Approval of the vote of no confidence means the end of the confidence relation with the Houses and entails the compulsory resignation of the Government.

The Government may be delegated by Parliament to adopt enactments having the force of law (legislative decrees); or else it may do so on its own initiative, but only in exceptional cases of necessity and urgency (decree-laws): decree-laws lose their force unless they are converted into law by the Houses within sixty days.

The National Council of the Economy and Labour, the Council of State and the Court of Accounts are ancillary organs of Parliament and the Government (arts. 99-100).

The State, the Regions, the Provinces, the Municipalities and the Metropolitan cities (the Metropolitan Cities have yet to be instituted) are jointly considered constituent entities of the Republic (art. 114). The entities other than the State are recognized as having the juridical status of “autonomous entities” with their own statutes, powers and functions.

The territorial entities all possess normative (statutory and regulatory), administrative and financial autonomy; only the Regions enjoy legislative powers. Of the twenty Italian Regions, five (Friuli-Venezia Giulia, Trentino-Alto Adige, Valle d’Aosta, Sardinia and Sicily) for historical-geographic or ethno-linguistic reasons enjoy special forms and conditions of autonomy, as defined in their respective Special Statutes adopted by means of a constitutional law (art. 116).

The division of legislative competence between State and Regions is defined in art. 117 as follows:

• a list is made of the matters in which the State has exclusive competence;
• a second set of matters, denoted as concurrent legislation, is identified for which legislative powers are invested in the Regions except as far as the determination of fundamental principles is concerned, which is reserved for laws of the State;
• in all other matters, the Regions have the power to legislate (residual competence).

As a general rule administrative functions (art. 118) are the prerogative of the Municipalities except when, in order to ensure unity of application, they are attributed to the other territorial levels or to the State in accordance with the “principles of subsidiarity, differentiation and adequacy”.

The work of interpretation carried out by the Constitutional Court has had a significant influence on the concrete application of these provisions, which were introduced by the 2001 constitutional reform.

Within the meaning of art. 101, justice is administered in the name of the people and the judges are subject only to the law.

For the purpose of safeguarding the autonomy and independence of the judiciary, the latter possesses an organ of self-government, the Superior Judicial Council (art. 104) and enjoys specific constitutional guarantees.

The jurisdictional function is performed by ordinary magistrates: the appointing of extraordinary or special judges is not allowed. The safeguarding of legitimate interests vis-à-vis the public administration is the task of the Council of State and the other organs of administrative justice, while the Court of Accounts rules on matters of public accounting (arts. 102 and 103).

The public prosecutor is obliged to take compulsory action in criminal cases (art. 112). Specific provisions exist to safeguard “due process of the law” (art. 111).

The Italian system of constitutional justice is based on a centralized model, in which control over the compatibility of laws with the Constitution is exerted by a single body – the Constitutional Court.

It is composed of fifteen judges, who remain in office for nine years. Five judges are elected by Parliament sitting in joint session, five others by each of the superior judicial bodies (three by the Court of Cassation, one by the Council of State, and one by the Court of Accounts), five are selected by the President of the Republic (art. 135, paragraph one).

The Constitutional Court is competent to rule (art. 134):

• on disputes related to the constitutional legitimacy of laws and of enactments having the force of law promulgated by the State and the Regions;
• on conflicts of attribution among the powers of the State and on those between the State and the Regions and among the Regions;
• on indictment for high treason and attempt against the Constitution of the President of the Republic. For these decisions the Court is supplemented by sixteen members drawn by lots from a list of forty-five citizens who are elected every nine years by Parliament;
• on the admissibility of requests to hold a referendum to repeal laws (Const. Law 1/1953, art. 2).

The issue of the constitutional legitimacy of a law may be brought before the Court through a jurisdictional authority in the course of a judgment (as an incidental proceeding). The Constitution also makes provision (art. 127) for direct recourse to the Court but only by the Government when it considers a regional law has overstepped the competence of the Region or by a Region in order to safeguard its own competence against laws of the State or of other Regions (active or principal proceeding, which may be undertaken within sixty days after the publication of the law in question).

A conflict of attribution may occur between the State and the Regions or among the Regions when an enactment other than a law or an enactment having the force of law (against which the State or Regions can appeal via a principal proceeding) is prejudicial to the competence of the State or the Region. Conflicts among the powers of the State that aim to delimit the sphere of attributions determined for the various powers by constitutional norms and may arise among bodies belonging to different powers which are competent to declare definitively the will of the power to which they belong (Law 87/1953, art. 37).