He has been an councillor to the Supreme Court of Cassation until 2003, when he switched to teaching – until 2017 – Ecclesiastical Law of the State and Comparative Ecclesiastical Law at the Law Department of the University of Bari "Aldo Moro" and at the school of specialization for the legal professions of the same University.
Former president of the Puglia section of the Central Tax Commission, he is now the president of the section of the Lazio Regional Tax Commission – Rome office.
Member of the Chamber of Deputies in the 11th legislature, he has been the author of the report to the Parliament of the "Massacres Commission ".
He has been a coordinating lawyer for the Puglia Region from October 2008 to January 2012.
He is a board member of the national committee of the "Committees for the Constitution", founded by Giuseppe Dossetti, of whom he edited and introduced the collection of writings “Constitution and resistance” (Rome, Sapere 2000, 1995).
He has been a member of various mixed commissions for relations between the State and religious denominations other than the Catholic Church (Waldensians Church, Jewish Communities, Buddhist Union).
Author of over two hundred scientific publications, he collaborates on various journals (including Il Foro italiano; Quaderni di diritto e politica ecclesiastica; Stato, Chiese e pluralismo confessionale; Forum di Quaderni costituzionali; Federalismi, Questione giustizia) ed opere collettanee quali Enciclopedia giuridica Treccani ed Enciclopedia del diritto Giuffrè. The monographs Confessioni religiose e intese. Contributo all’interpretazione dell’art. 8 della Costituzione (Bari, Cacucci, 1990), Tutela della personalità e diritti della coscienza (Bari, Cacucci, 2000) e Eguaglianza e diversità culturali e religiose. Un percorso costituzionale (Bologna, Il Mulino, 2006) were reported among "the 12 books of the year of legal science" by the jury of the Club of jurists, chaired by Pietro Rescigno.
The latest books: Diritto pubblico delle religioni, Eguaglianza e differenze nello Stato costituzionale (Bologna, Il Mulino, 2012), now in its second edition, and the La lotta per la laicità. Stato e Chiesa nell’età dei diritti (Bari, Cacucci, 2017).