Deliberation is widely believed to enhance democracy by helping to refine the “public will,” moving its participants’ policy attitudes closer to their “full-consideration” policy attitudes—those they would hypothetically hold with unlimited information, to which they gave unlimited reflection. Yet there have also been claims that the social dynamics involved generally “homogenize” attitudes (decreasing their variance), “polarize” them (moving their means closer to the nearer extreme), or engender “domination” (moving their overall means toward those of the attitudes held by the socially advantaged). These are attitude changes that may often be away from the participants’ full-consideration attitudes—and may thus distort rather than refine the public will. This paper uses 2,601 group-issue pairs in 21 Deliberative Polls to examine these claims. Reassuringly, the results show no routine or strong homogenization, polarization, or domination. What little pattern there is suggests some faint homogenization, but also some faint moderation (as opposed to polarization) and opposition (as opposed to domination)—as, we argue, is to be expected when the outside-world forces shaping pre-deliberation attitudes are slightly more centrifugal than centripetal. We take pains to lay out a theoretical basis for these interpretations and to probe our results, highlighting, among other things, deliberation’s role in undoing outside-world effects on pre-deliberation attitudes and the observed homogenization’s, polarization’s, and domination’s dependence on deliberative design.

Appendices A-C