Counting on my vote not counting: Expressive voting in committees

How do voting institutions affect incentives of committees to vote expressively? We model a committee that chooses whether approve proposal some members may consider ethical. Members who for the receive expressive utility, and all pay cost if is accepted. Committee have different depths reasoning. Under certain sufficient conditions, predicts features reduce probability member being pivotal – namely, larger size, or more restrictive rule raise share votes in favour proposal. A laboratory experiment with charitable donation framing presents evidence line these results. Our structural estimation recovers distributions altruistic preferences, as well depth reasoning, across individuals.