Going dark? Analysing the impact of end-to-end encryption on the outcome of Dutch criminal court cases

Abstract Law enforcement agencies struggle with criminals using end-to-end encryption (E2EE). A recent policy paper states: “while encryption is vital and privacy and cyber security must be protected, that should not come at the expense of wholly precluding law enforcement”. The main argument is that E2EE hampers attribution and prosecution of criminals who rely on encrypted communication - ranging from drug syndicates to child sexual abuse material (CSAM) platforms. This statement - in policy circles dubbed ‘going dark’ - is not yet supported by empirical evidence. That is why, in our work, we analyse public court data from the Netherlands to show to what extent law enforcement agencies and the public prosecution service are impacted by the use of E2EE in bringing cases to court and their outcome. Our results show that in cases brought to court, the Dutch courts appear to be as successful in convicting offenders who rely on E2EE as those who do not. Our data do not permit us to draw conclusions on the effect of E2EE on criminal investigations.