[rootusrootus]

> Also the reverse problem: The current resident gets the ballot and tries to vote with it.

Any kind of double voting shenanigans should be pretty straightforward to detect. So when it happens, you [at least] invalidate the second attempt, and forward the details over to the police for investigation and prosecution.

The thing about voting is that most of the legwork in verifying voters is done in advance of any election. By the time you get to ballot-casting, the hard part is done.

[ars]

Why would there be double voting? The person whose ballot was taken will not vote elsewhere. It's a single vote, just not by the actual voter.

[rootusrootus]

If you want to affect the outcome of the election, you will need to change a lot more than a single vote. Each ballot you steal, next to worthless all by itself, opens you up to detection, and vote tampering comes with heavy penalties.

You need to find a systemic vulnerability, otherwise the risk is much too high and the odds of success much too low. Vote-by-mail isn't actually a worry unless you have an ideological position based on the current election, you should really worry about the electronic voting machines used in many places that have in-person voting. The potential for systemic fraud there is much, much higher.