A TRUST-MINIMIZED PRIVACY-PRESERVING BLOCKCHAIN VOTING SYSTEM ON ETHEREUM USING ZK-SNARKS WITH CLIENT-SIDE PROVING AND RELAYER-BASED UNLINKABILITY

Abstract

Public blockchains give elections a tamper-evident bulletin board, yet the transparency that makes results auditable also threatens ballot secrecy and voter anonymity. Prototype systems that pair Ethereum with zero-knowledge proofs commonly reintroduce trust through the back door: a server that holds voter secrets and generates proofs, transactions that link a voter wallet to a ballot, plaintext candidate choices in public calldata, and nullifiers that are accepted without being cryptographically bound to the verified proof. This paper proposes a trust-minimized voting architecture for small and medium electorates that removes all four weaknesses by construction. Eligibility is proven inside a Groth16 circuit against an on-chain Poseidon Merkle registry; proofs are generated entirely in the voter's browser through a WebAssembly prover so the voting secret never leaves the device; ballots are cast as hiding commitments and submitted through ERC-4337 relayers so no voter address ever appears on chain; and the double-vote nullifier is recomputed inside the circuit and checked against the proof's public signals. We give the full protocol, a property-by-property security analysis against a concrete threat model, and an analytical evaluation grounded in recent published benchmarks, which projects per-ballot costs of roughly 352,000 gas and sub-six-second casting latency on a rollup. The design is intended as the specification for a subsequent thesis implementation.