An informational role of supermajority rules in monitoring the majority party's activities

There often exists a supermajority rule that enables the minority party to delay or prevent a vote on a bill. I construct a two-period model consisting of a representative voter, self-interested parties, and a media outlet. In the model, the majority party has an incentive to misrepresent the voter's optimal policy. I show that the minority party's attempt to block a vote (e.g., a filibuster) can signal this misrepresentation. Interestingly, the key is that the minority party and the mass media are complementary in creating the signal. Overall, the results suggest that supermajority rules could be beneficial even for the majority of voters.