Early in his career, Roberti worked as anti-mafia prosecutor in Naples. In 2007, he managed to arrest mafia boss Edoardo Contini, at the time considered one of Italy's 30 most dangerous fugitives.[3]
Roberti served as National anti-mafia and anti-terrorist prosecutor from 2013 to 2017.[4] During his time in office, he led a 2016 effort of Italian, Colombian and U.S. police to seize 11 tonnes of cocaine and arrest 33 people from a mafia-linked ring which refined the drug in the jungles of Colombia and smuggled it out in containers of tropical fruits.[5] He also worked to ensure the mafia is blocked from playing any role in reconstruction after the August 2016 Central Italy earthquake that killed nearly 300 people.[6]
In2019 Robert has been elected as a member of the European Parliament.[7] In the European Parliament, he has since been serving on the Committee on Legal Affairs (JURI). In addition to his committees assignments, he is a member of the parliament's delegations for relations with the Mashreq countries and to the Parliamentary Assembly of the Union for the Mediterranean. He is also a substitute member of several other EP committees, including LIBE (Committee on Civil Liberties, Justice and Home Affairs).