Deliberation, single-peakedness, and the possibility of meaningful democracy: Evidence from deliberative polls

Majority cycling and related social choice paradoxes are often thought to threaten the meaningfulness of democracy. Deliberation can protect against majority cycles - not by inducing unanimity, which is unrealistic, but by bringing preferences closer to single-peakedness. We present the first empirical test of this hypothesis, using data from Deliberative Polls. Comparing preferences before and after deliberation, we find increases in proximity to single-peakedness. The increases are greater for lower- versus higher-salience issues and for individuals who seem to have deliberated more versus less effectively. They are not merely a by-product of increased substantive agreement (which in fact does not generally increase). Our results are important, quite apart from their implications for majority cycling, because single-peakedness can be naturally interpreted in terms of an underlying issue dimension, which can both clarify the debate and allow a majority-winning alternative to be interpreted as a median choice and thus as an attractive compromise.