There's issues that are pretty fundamental with the black-box approach that the electronic ballot becomes. Paper and transparent ballots can be scrutinized pretty easily, but once you have a black box that might also be connected to the internet there's nothing you can really trust.
Us "computer folks" convincing ourselves is the easy part. Maybe after enough studying of the system, I'd be absolutely sure that my vote was counted, but what would the other 90 % of the population think? This not a "people are stupid" argument, a brain surgeon or nuclear physicist or philosopher isn't going to put in the effort to understand fully homomorphic cryptography, hardware-based security, etc. Why should they?
The alternative works perfectly fine and it's so easy to explain. It's obvious to anyone, no matter their level or field of education, how their vote makes it from their hand into the tally, what prevents it from being misused and what they can do to further reduce that already tiny probability.
You can see, feel and experience the technical measures keeping your vote safe. The people keeping their eyes on the ballot box alp day may literally be your neighbours, as are the people counting. You can reason about their motivations, you can theorise in your head about what lengths you'd have to go to in order to change even a few votes and how unlikely you would be to succeed.
The biggest danger to elections, ultimately, isn't the risk of cheating. It's the risk of losing the people's trust.
(I'm in the local election commission (that's layer 2 out of 4 in our particular election management hierarcy), we just had a big referendum, everyone keeps asking me about online elections so this rant was fresh on my mind)
In any system, I suspect it is possible. There are strategies that allow doing private set intersections (or similar): https://en.wikipedia.org/wiki/Private_set_intersection (i.e. a set with one member is "you", and you can check to see if you're in that 764, without knowing who the others are)
I'm not sure what strategies would also allow you to not reveal to the vote collectors where your vote went, but there might be something.
> Private set intersection is a secure multiparty computation cryptographic technique[1] that allows two parties holding sets to compare encrypted versions of these sets in order to compute the intersection. In this scenario, neither party reveals anything to the counterparty except for the elements in the intersection.
Revealing even elements in the intersection, if that means revealing individual votes, breaks ballot secrecy.
I think such a system could still work, but just like the voter has to go to the booth alone to vote, they must go the booth alone to verify.
That being said I think the Estonian voting system does a decent job of being trustworthy. Publishing the source code is a big step to the better as well. As far as I knew the system was written in Java but seems like they have upgraded it in Go. Good job! Probably the best in the world.
I might be missing something obvious but I'm not quite seeing the logical inconsistency between their two goals. Note they're only asking to verify their own vote, not to verify every other person's vote. For that, isn't it enough for authorities to announce a product of large primes, letting each person verify that their own prime was in the set? At each stage, the machines only report the product of primes up the chain, not the individual ones.
It seems to me the difficulty is with the fact that we have so many places to hide malicious things with modern technology (tiny electronics, firmware, etc.), not a logical incompatibility between the goals. If you had some sort of abacus that did all this mechanically without reprogrammability... or a large computer whose logic was fully verifiable... then everyone could inspect the machine and verify that it behaves correctly prior to elections, and e.g. a camera/observers/etc. can ensure no tampering occurred with the machine until the tallies were conducted.
BTW, the source code we're talking about could easily be enormous, especially if you want the machines' firmware to be open too. Reviewing that source code would be a huge task. And you still have the problem of being unable to validate that the actual object code run in production corresponds to the source code you reviewed. And the public won't believe any of it anyway.
However, the Estonian governement has made a different choice and I salute that they are at least trying to do everything by the book and in the right way. Publishing the source code is a part of that. Estonia is a high-trust society (which is an incredible achievement in itself, considering they were a province of the Soviet Union only forty years ago) and they have the most functional e-identity system in the World. Voting is just a part of it. It does make many things easier and also helps economy if you can trust your fellow man.
Faking paper ballots is totally doable, but you can take various precautions to make that very difficult. For example, you can deliver ballots to polling locations in sequentially-numbered packs and shuffle them at the voter sign-in desk: by shuffling the packs before delivery, by having the elections judges record which packs they got and which numbers went unused, by making them sign ballots prior to placing them on the sign-in table, and so on, you can make it very difficult for elections administration staff to later replace those paper ballots. But you're going to need timely, partial or full hand-count audits in order to make it necessary to replace paper ballots in order to replace results.
Election security is pretty expensive, but compared to the _value_ of elections, it's nothing.
In code, you have no insight into what actually happens.
trivia: did you know that a tear in any of the pages of your passport renders it invalid?
> The intention behind this repository is to make source code of the Estonian online voting system available for public review.
> The repository is not used for active development, but will be kept up to date, so the code that can be found here is the code that is used for election.
The repository is not used for active development, but will be kept up to date, so the code that can be found here is the code that is used for election. As the voting system used for legally binding elections must strictly follow the legislation, the actual development of Estonian I-voting system and I-vote verification application is supervised by State Electoral Office of Estonia. Please refer to www.valimised.ee for further information.
That still leaves tons of other technical problems to address, like security of mail-ballots / absentee ballots, the security of ballot boxes used for early voting (because you probably cannot run the above manual partial audit due to then having nightly results available to the public; or maybe you accept that), voter registration, etc.
Your ID card contains a private key, you use that key to sign a transaction. It doesn't matter that machine you are running on is compromised as these details can be verified at a later date.
Example A: You vote for candidate A, but software changes to candidate B and software displays that you voted for candidate A. At any later time you can check with an independent device and look at the transaction finding out that it was altered with and retract your vote / change it.
Example B: How do you know your vote was counted? Publish a hash and the signature of every vote, recompute the final tally and compare with all the votes. If your vote is not in the final tally the hash will be different and you can visibly see your vote in the dataset as every transaction is published. To preserve privacy each round has a number, private key + number -> new key so each fingerprint will be unique between votes.
I've spent a lot of time thinking about this problem, and my conclusion is that cryptography alone is not the solution, for reasons like:
1. The public needs to believe it, and hypertechnical solutions are a hard sell.
2. Any blockchain approach needs to preserve the secrecy of the ballot, otherwise you get all the problems you can expect of non-secret votes (coercion, vote buying, shaming network effects).
3. You still need to have the cryptographic rubber meet the physical road _somewehere_ -- it has to, otherwise the need for vote secrecy means that the results can be entirely fictitious and pre-programmed and there is no way to check!
I.e., you can have a paperless blockchain solution IFF you abandon vote secrecy. That is a very tough to swallow pill.
On the other hand, if you accept paper ballots and manual partial audits as part of the solution, then blockchain can have a role to play. For example, the machines could display a blockchain head every 50 ballots cast, and voters take a copy of the blockchain head visible to them, then after the election the public can verify the integrity of the blockchain, and the fact that you only get running tallies every 50 ballots means you get vote secrecy.
A system that uses paper ballots and partial manual audits can be explained to the public, and the public can develop confidence in it. Blockchains can then add a good deal of confidence: the blockchain tells you that the tallies were not modified after the fact, and the partial manual audit tells you to an acceptable level of statistical confidence that the digital cast vote record contains the actual paper ballots _as marked and cast_ by voters.
This is false. I know this is a common thought here on HN because some formerly popular youtuber did a video about this that was regularly reposted here, but he was wrong in theory back then and it is wrong in practice today. Secrecy and anonymity and verifiability are no longer mutually exclusive as anyone who is well versed in modern cryptography will be able to tell you.
Also, you still have to convince the public.
There is no problem that electronic voting solves that paper ballots and scanners do not, and the latter are not only more secure but are seen to be more secure. Trust is essential in a voting system and only paper ballots provide the necessary level of trust.
There is a specific problem with mail-in voting and disabled voters, for example elderly people who can't go to the polls and can't get an electronic ballot marker. 25 US states deliver ballots electronically and 15 allow electronic voting for this specific case [1].
[1] https://www.ncsl.org/elections-and-campaigns/electronic-ball...
In the end, you always must trust humans.
This seems to make a pretty dramatic change to the election protocol, no?
Consider example A': You vote for candidate A, but later realize that you hate candidate A. You repudiate your recorded vote for candidate A.
What should happen?
That means it doesn't matter one bit how correct you are if the regular Joe does believe you tricked. Adding computers into the mix always makes this worse. And again, this is not something you can fix with clever solutions and cryptography (that admittedly fascinates me nonetheless), the problem is that people can't see electricity generally and I something at the scale of a computer, even if you could it would be utterly meaningless.
This is why the paper ballot system is so glorious in its stupid inefficiency, because it spreads the trust in a way any adult who has mastered object permanence can verify for themselves. Invite the conflicting parties to monitor and have them begrudgingly admit their defeat in the face of the simple, inefficient but agreeable process.
This is why I as a cryptography fan, programmer and hardware guy think electronic voting is not up to the task for high stakes elections.
I mean that's too abstract and philosophical of a problem when talking about voting machines/software: there are much more prevalent and concrete risks including but not limited to APT-grade breach/espionage if your country is important enough, and the various other issues (some in your comment itself).