[jasonlaramburu]

>Even if that was possible, after the vote closes the ballots are counted and the amount must match the number of people who voted, so the result would be invalidated.

So an attacker could potentially invalidate hundreds (or thousands) of votes by stuffing a single fake ballot into the box? This seems like the illusion of security.

[seszett]

To follow up on this now that the election has been done, here are the results and the detail of invalidated votes: https://www.conseil-constitutionnel.fr/decision/2022/2022195...

About 10 000 votes have been invalidated in total, which is an order of magnitude less than the smallest difference between two candidates, and 40 times less than the amount of votes which decided which candidates are going to be present for the 2nd turn.

Only one voting office reported a significant discrepancy between the amount of ballots and the amount of voters, resulting in 475 invalidated votes.

[throw0101a]

> So an attacker could potentially invalidate hundreds (or thousands) of votes by stuffing a single fake ballot into the box? This seems like the illusion of security.

In Canada poll workers initial the ballots, and the ballots have serials numbers on them and a stub (which also has the S/N) that is torn off by poll worker:

> The election worker checks their initials and the assigned polling station number on the back of the ballot; compares the counterfoil number against the stub number in the booklet and makes sure they are the same; takes off the counterfoil and tears it up; and gives the ballot back to you to put in the ballot box. You slide your ballot into the ballot box where it is mixed in with other ballots. No one will know how you voted.

* https://www.elections.ca/content.aspx?section=vot&dir=int/sa...

So there's a record of which ballots were put in via proper workflow.

If there's a discrepancy the non-proper ballots can be identified and removed.

From Elections Canada:

* https://www.youtube.com/watch?v=lqu8ONkWQBE

* https://www.youtube.com/watch?v=cbc_n8Ys_CA

[seszett]

I'm not sure exactly what happens, it's never happened when I was counting ballots.

Invalidating a box could result in up to a thousand votes being discarded indeed, which is quite small though for a national election.

[jasonlaramburu]

>Invalidating a box could result in up to a thousand votes being discarded indeed, which is quite small though for a national election.

I don't know what are the typical margins of victory for French Elections. In the 2000 US Presidential Election, George W. Bush won the Presidency by a margin of 537 votes in Florida. If the US had implemented French style balloting, a single attack of this kind in a heavily Republican district of Florida could have easily swayed the election to Gore.

[seszett]

French elections are decided on ~40 million total votes. Margins are much larger than a thousand votes.

[malka]

the box is invalidated. If enough boxes are unvalidated, the ballot is probably cancelled, and rescheduled.

[malka]

It would require a lot of effort to do this at scale, and it could not go unnoticed. Probably not perfect, but I dont see a better system.