Combining theory and experiments, we examine decision-making with endogenous deliberation across different voting rules: consensus and veto unanimity, and simple majority. Before voting, asymmetrically informed agents choose whether to engage in potentially costly communication to aggregate their private information. In line with existing studies, we find that free communication minimizes differences in decision-making across rules. In contrast, with costly communication, differences in decision-making re-emerge as the voting rules affect communication and private information aggregation. Consensus unanimity frequently outperforms the other rules because it induces more communication among agents. This work provides a new rationale for the legitimacy of the commonly used consensus unanimity voting rule in jury trials.