Because the judiciary and police play complementary roles in criminal investigations, Eurojust continued to cooperate closely on operational work and analytical projects throughout 2020 with Europol, the European Union Agency for Law Enforcement Cooperation.

National judicial authorities requested Europol to be a full partner in 40 large actions coordinated through Eurojust in 2020, including the JIT to dismantle EncroChat, an encrypted phone network widely used by criminal networks.

Beyond close cooperation in casework, Eurojust and Europol worked together on strategic projects to provide efficiency and synergies in the fight against complex cross-border crimes, such as encryption. The SIRIUS project, which supports law enforcement and judicial authorities with knowledge-based products on cross-border access to electronic evidence from US-based Service Providers, has expanded via the formalisation of the partnership between the two agencies. Eurojust became a full co-beneficiary to the second phase of the SIRIUS project lasting until mid-2024.