Adjudication with Rational Jurors

We analyze a mechanism for adjudication involving majority voting and rational jurors, who might not be willing to exert effort to properly judge a given case. The mechanism rewards jurors who vote in accordance with the final verdict and optionally punishes jurors who do not. We give bounds on the number of jurors and payments that are sufficient to guarantee a bounded error rate of the resulting adjudication. We show that the mechanism results in a non-trivial adjudication for sufficiently large payments provided that sufficiently many jurors are well-informed (on average). We consider different classes of jurors and show how to instantiate the payments to bound the error rate of the resulting system. Our work has applications to decentralized dispute resolution systems like Kleros.