Silence as evidence?

In both international as well as (Dutch) national law, a suspect is not obliged to answer questions and is not required to incriminate themselves. Nevertheless, the European Court of Human Rights (ECtHR) and the Dutch Supreme Court allow that, in certain cases, adverse inferences may be drawn from a suspect’s silence. The legal frameworks surrounding this issue are developed based on specific cases and are therefore hard to generalise. This has led to critical commentary in the literature, suggesting that too much weight may be attributed to a suspect’s silence in relation to the evidence in a case. Against this background, the central research question of this dissertation is: What role does a suspect’s silence play in the evidentiary decisions of Dutch trial judges, and how can that role be understood and evaluated both legally and logically? In this dissertation I explore empirically how Dutch criminal judges use a suspect’s silence in practice, and reflect on that use through both legal frameworks and theoretical perspectives on evidence. The empirical research consists of a systematic analysis of trial judgements in money laundering cases (Chapter 2) and theft cases (Chapter 3), as well as semi-structured interviews with twenty criminal judges across the Netherlands (Chapter 4). The case law of the ECtHR and the Dutch Supreme Court (Chapter 1) provided the legal framework. Chapter 5 offers a theoretical reflection on the findings, drawing on three theories of evidence: the argumentative approach, the narrative approach, and Bayesian reasoning. Two roles of silence in evidentiary decision-making by Dutch trial judges were identified in this research. The first is silence as the absence of a (plausible) alternative explanation for incriminating evidence. In an adversarial process, suspects have the opportunity to present their side of the story, which can influence the judge’s assessment. A suspect that remains silent misses that opportunity, which can have several consequences depending on the circumstances of the case. This can be consistent with ECtHR and Dutch Supreme Court jurisprudence, provided that the evidence is sufficiently strong on its own and that silence does not carry disproportionate weight. According to the presumption of innocence, the burden of proof lies with the prosecution. Only after this burden is met may a suspect be expected to provide an explanation and may silence have negative consequences. Therefore it is important to critically assess the evidence used and the role silence may have played in the evidential reasoning. The second role of silence is likely smaller and more subtle: silence as an “indication of guilt.” This role is not part of the adversarial, but rather the constructive side of the studied theories of evidence. It stems from generalizations such as “those who are silent are guilty”. In this way, silence may subtly contribute to meeting the standard of proof under Dutch law (Article 338 of the Dutch Code of Criminal Procedure). Non-legal factors that can influence a judge's reasoning are described in the literature as part of the judge’s subjective conviction, and are seen as an unavoidable aspect of judicial decision-making. Even the standard of “beyond reasonable doubt” – considered by some to be more objective than the judge’s personal conviction – is still partly a personal assessment within legal boundaries. This is not necessarily problematic, but it does require that legal standards – such as reasoning and evidentiary thresholds – are consistently upheld. Silence, in this context, can and should only play a very minor role, both legally and logically, since silence in itself proves nothing. Suspects may have many reasons to remain silent that are unrelated to guilt.