There are many design goals for an e-voting system. My question concerns a conflict between 2 particular goals:
- A voter should be able to verify that their vote was correctly tallied
- A voter should not be able to prove how they voted (to prevent vote selling)
I've looked into various e-voting systems and none of them appear to be able to satisfy these 2 goals simultaneously.
Some researchers argue that end-to-end auditability and receipt-freeness should be considered to be orthogonal properties. (Wikipedia)
Is this an unsolved problem?