International and European sources
The general principles of the Italian law on religions are derived from international and European sources on the one hand, and the Constitution of 1947 (in effect in 1948) and its interpretation by the Constitutional Court on the other hand.
Regarding international and European law, it is important to mention the standards that protect religious freedom (particularly article 18 of the Universal Declaration of Human Rights of 1948 and article 18 of the United Nations International Covenant on Civil and Political Rights of 1966 and especially article 9 of the European Convention on Human Rights) and prohibit discrimination on the grounds of religion (article 14 ECHR).
Fully recognising the European Convention on Human Rights system also implies that Italy recognises the jurisdiction of the European Court in Strasbourg (see an example in the case of Pellegrini v. Italy of 20 July 2001).
At the same time, as a member of the European Union, Italy recognises and applies Community law in all of its aspects including its repercussions on internal law on religions (refer to M. Ventura, La laicità dell’Unione europea. Diritti, mercato, religione, Torino, Giappichelli, 2001 and M. Ventura, "Protectionnisme et libre-échangisme. La nouvelle gestion juridique de la religion en Europe" Conscience et liberté, 64, 2003, p. 122-132, on this subject).
Constitutional principles that should be mentioned:
The principle of equality: "All citizens have equal social status and are equal before the law, without regard to their sex, race, language, religion, political opinions, and personal or social conditions" (article 3§1);
The principle of freedom of religion: "Everyone is entitled to freely profess religious beliefs in any form, individually or with others, to promote them, and to celebrate rites in public or in private, provided they are not offensive to public morality" (article 19);
The principle of freedom of religious associations: "For associations or institutions, their religious character or religious or confessional aims do not justify special limitations or fiscal burdens regarding their establishment, legal capacity, or activities" (article 20);
The principle of mutual recognition of State sovereignty and Church sovereignty: "State and Catholic Church are, each within their own reign, independent and sovereign" (article 7§1);
The principle of bilateral pacts in relations between the Catholic Church and the Italian State: "Their relationship is regulated by the Lateran pacts. Amendments to these pacts which are accepted by both parties do not require the procedure of constitutional amendments" (article 7§2);
The principle of the "equal freedom" of religious denominations: "Religious denominations are equally free before the law" (article 8§1). A Constitutional court decision of 18 April 2005 has declared the unconstitutionality of article 403 of the penal code which sets out heavier sanctions for offences against the Catholic religion than those which are applied for the same offence committed against other religions (Sentenza 18 aprile 2005, n.168);
The principle of religious autonomy: "Denominations other than Catholicism have the right to organize themselves according to their own by-laws, provided they do not conflict with the Italian legal system" (article 8§2);
The principle of bilateral relations between non-Catholic religious denominations and the State: "Their relationship with the State is regulated by law, based on agreements with their representatives" (article 8§3).
Subsequently the Constitutional Court deduced an absolute principal of secularism from the explicit constitutional standards (decision of 12 April 1989 No. 203).