Today, several social movements in western democracies argue that traditional representative democracy has failed to adequately represent the will of the “people”, and instead support direct democracy as the only political system to restore the will of the majority. We analyze under what conditions the policy – a vector of decisions on every issue – implemented by the winner of a bipartisan electoral competition coincides with the policy that citizens would choose by means of direct democracy. We find necessary and sufficient conditions for this equivalence to hold, implying that, as long as at least one of them is not fulfilled, a divergence of outcomes between direct and representative democracy arises. The first condition requires that the outcome of majority voting issue-by-issue is the Condorcet winner relative to the voters’ preference profile over the set of policies. The second requires that either that outcome is the preferred policy for at least one of the candidates, or that candidates’ preferred policies differ on every single issue. We reinterpret some findings in the literature in the light of our model and present them as potential reasons why the equivalence between direct and representative democracy may fail.

中文翻译：

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通过代表制实施直接民主

如今，西方民主国家的一些社会运动认为，传统的代议制民主未能充分代表“人民”的意志，转而支持直接民主作为恢复多数人意志的唯一政治制度。我们分析了两党选举竞争获胜者所实施的政策（每个问题的决策向量）在什么条件下与公民通过直接民主选择的政策相一致。我们发现这种等价性成立的必要和充分条件，这意味着只要至少有一个条件不满足，直接民主和代议制民主之间的结果就会出现分歧。第一个条件要求，相对于选民对一系列政策的偏好，逐个问题的多数投票结果是孔多塞获胜者。第二个要求要么该结果是至少一位候选人的首选政策，要么候选人的首选政策在每个问题上都不同。我们根据我们的模型重新解释文献中的一些发现，并将它们作为直接民主和代议制民主之间的等同性可能失败的潜在原因。