Ignacio de Lucas has been a public prosecutor for more than 25 years, and is the former Deputy Head of the Special Anti-Drug Prosecution Office in Spain. An expert in international cooperation, he was the coordinator of the Ibero-American Network of Anti-drug Prosecutors (RFAI) (2014–2023) – an operational network promoting transnational investigations, comprising 22 national prosecution offices across Latin America and the Iberian Peninsula. He was also the contact point for the European Judicial Network in Criminal Matters (EJN) (2007–2011 and 2021–2023), IberRed (2014–2013) and the European Multidisciplinary Platform Against Criminal Threats (EMPACT) to combat high-risk criminal networks (2022–2023).

In addition to his prosecutorial work at national level, he was the Senior Coordinator of the Central American Network of Prosecutors against Organised Crime at the United Nations Office on Drugs and Crime (UNODC) in Panama (2011–2013), and has also worked as a seconded national expert in the Judicial Cooperation Unit of the European Commission in Brussels (2005–2007).

He has participated in a number of Financial Action Task Force (FATF) and IMF mutual evaluations as a legal expert, focusing on the investigation and prosecution of money laundering, confiscation and international cooperation. He has regularly provided technical support on money laundering to prosecution offices in Latin America, Central Asia and the Middle East, including the design and implementation of capacity building programmes aimed at prosecutors and investigators. In July 2023, he was appointed European Prosecutor from Spain by the Council of the EU.