Mr Kessler was appointed Director General of the European Anti-Fraud Office of the European Commission (OLAF) on 14 December 2010.

He is an Italian magistrate. His varied career includes experience as a Public Prosecutor, serving in international missions, and as an elected member of the Italian national parliament. He was Public Prosecutor at the criminal courts of Trento, Bolzano and at the Anti-Mafia Department in Sicily from 1986 until 1998, dealing with organized crime, corruption and financial crimes. From 1998 to 1999, he was the Deputy Head in charge of Police and Justice at the Organisation for Security and Co-operation in Europe (OSCE) Kosovo Verification Mission in Pristina. As a judicial expert he participated in several European Commission and Council of Europe evaluation missions in Eastern Europe.

In 2006, Mr Kessler was appointed by the Italian government as High Commissioner to Combat Counterfeiting and Piracy, where he served for two years. He served in the Italian Parliament from 2001 until 2006. He authored bills on the International Criminal Court, the European Convention against corruption, the International Judiciary Cooperation and on the European Arrest Warrant. At the same time, he was a member of the OSCE Parliamentary Assembly and Vice-President from 2003. He participated in and led International Election Monitoring missions in the USA and in many other OSCE countries. In 2008, he was elected member and then President of the Legislative Assembly of the Autonomous Province of Trento and in 2010 he was also the President of the Conference of European Regional Legislative Assemblies.

Mr Kessler obtained a master degree with honours in law at the University of Bologna, with a dissertation in constitutional law. A native of Trento, Italy, Mr Kessler is married with two children. In his free time he enjoys cycling and trekking.