Publicly verifiable delegative democracy with secret voting power

Abstract

In a democratic setting, we introduce a commitment scheme which allows for transparent validation of transfers and reversible delegations of voting power between citizens without sacrificing their privacy. A unit of voting power is publicly represented by the Merkle root of a tree consisting of its latest owner's public key, a random nonce and the Merkle root of the tree of its previous owner's public key and random nonce and so on. A transition includes the input units, their owner's public keys and signatures, the hashes of their nonces and the output units generated with the new owners' public keys and random nonces. In case of a delegation, the receiver provides the sender with the hashed random nonces and hashed public keys for the output units. In case of a transfer, only the precomputed output units are provided by the receiver. In a reversal, a historical owner reveals the hashes of the nonces and public keys that resulted in the subsequent units. To vote, the owner reveals the actual nonces and public keys.