A lot has been said about paper ballots and paper trails in the last few years. There are many good arguments for having the paper, including the ability to audit the machines, transparency of the vote counting, recount capability, and voter confidence. But there is another reason why it is important to have paper ballots (which I prefer over VVPAT on a DRE), and that is simply that electronic ballots are more fragile than paper. A power glitch can cause a magnetic memory card to lose its data. So can a magnet. There are multiple ways that electronic data can be come corrupted or lost. Paper is not immune to corruption or loss, but there are two big differences. The loss of many paper ballots is more likely to be noticed immediately, and a loss event is likely to effect fewer paper ballots than electronic votes. One memory card can hold thousands of votes, and such a card is significantly smaller than a deck of cards.
Look at the New Mexico election in 2004. The Washington Post published a story about how 678 votes were completely lost due to a programming error of the electronic voting machines by election staff that was not properly trained. Arguments were made by different people on different sides of the issue about why these votes were lost, or whether they in fact were really lost. The bottom line is that if people had voted with paper ballots (even if they were marked using a ballot marking electronic touchscreen machine), then the election workers would not have even been in a position to cause the votes to be lost.
Another example is Carteret County, NC where, as many news stories reported, 4,532 votes were lost due to faulty electronic equipment.
As we approach another election this fall, we have to consider the possibility of close races and lost votes. With so much at stake, it is a shame that we have to worry about whether or not computers will crash, memory cards will die, or election workers will make mistakes that could cause the wrong results to be tallied. Equally frighting is the possibility that the election will simply fail due to an unecoverable problem.
I don't think enough emphasis has been placed on the problem of recovery in the discussion of e-voting. It is easier to recover from election problems if we have paper ballots to count and machines to audit against paper than if all we have are electronic tallies.
