Ed Cone interviews the security guru Bruce Schneier about voting machines:
There are a couple of reasons that things like automatic teller machines and gas pumps are more secure. The first one is, there’s money involved. If someone hacks an ATM, the bank loses money. The bank has a financial interest in making those ATMs secure. If someone hacks a voting machine, nobody loses money. In fact, half the country is happy with the result. So it’s much harder to get the economic incentives aligned.
The other issue about voting machines is that ballots are secret. A lot of the security in computerized financial systems is based on audits, based on being able to unravel a transaction. If you go to an ATM and you push a bunch of buttons and you get out ten times the cash you were supposed to, that’s a mistake, but that mistake will be caught in audit, and likely, you will be figured out as the person who got the money by accident, and it will be taken out of your account. Because ballots are secret, a lot of the auditing tools that we in the community have developed for financial systems don’t apply.