The study challenges the widespread assumption that the decision rule of ‘consensus’, whereby decisions are made by “tacit consent”, i.e. without voting and through the absence of open dissent, attributes veto power to each decision-maker. It addresses this assumption from a conceptual, an analytical and an empirical point of view and reassesses the democratic value of this decision rule and its empirical applicability in this light.The main argument of the study is that veto options are restricted in so many ways under the rule of consensus that this general assumption is misleading. It is shown that the power to veto collective decisions under consensus rule is severely limited by various social mechanisms and norms, that it is furthermore asymmetrically distributed amongst decision-makers and additionally de-activated in a large share of empirical cases by an effective ‘shadow of majority voting’.A comprehensive assessment of input- and output-related dimensions of democratic legitimacy shows how the equality of participation and of influence and the norms of transparency and accountability are violated by the restricted veto options and by the ambiguous preference order that follows from the peculiar logic of this decision rule, while the rule’s efficiency is striking and group commitment is typically not lower than under voting rules. Considering strengths and weaknesses of the decision rule, its suitability in various political contexts is discussed.