Law Technology

voting ID requirements and the Supreme Court

By Dan Wallach

Last week, I posted here about voter ID requirements.  There was a case pending before the U.S. Supreme Court on the same topic.  It seems Indiana was trying to require voters to present ID in order to vote.  Lawsuit.  In the end, the court found that the requirement wasn’t particularly onerous (the New York Times’s article is as good as any for a basic summary, or go straight to the ruling).

Unsurprisingly, there has been a lot of hang-wringing on this (see, for example, this New York Times unsigned editorial).  We can expect similar legislation elsewhere now that the Court has made it pretty difficult to challenge these sorts of laws (see, for example, the ongoing battle to pass this sort of legislation in Texas).

As I wrote last time, I’m not particularly opposed to voters being required to present ID.  However, ID needs to be easy to get for anybody who is elgible to vote.  For most people, this is easy.  The big question we’d all like to know is the size of the population for which it’s not easy.  Consider, as a hypothetical example, an elderly Texas woman who never drove a car.  If she’s over 75 years old, the state’s centralized birth certificate registry won’t (officially) have her records.  It could well require detective work to produce sufficient documentation to get her a state ID card.  Who’s going to pay for that?

The big technical question, of course, is whether the root desires behind the voter ID requirement can be addressed in some more effective fashion than ID requirement.  What are those root desires?

1. Prevent legitimate citizens from registering to vote and voting in more than one locale
2. Prevent registered voters from casting multiple votes in their own name
3. Prevent registered voters from impersonating other registered voters
4. Prevent anyone, including malicious poll workers, from casting votes on behalf of registered voters who have chosen not to vote
5. Prevent non-eligible people (non-citizens, felons, etc.) from registering to vote
6. Detect changes in registered voters’ eligibility status, quickly and accurately

Which problems can be solved by purple ink on a voter’s thumb?  #1 and #2 are readily solved, since a second attempt to vote will be forbidden.  #3 is disincentivized, because the impersonator will be unable to vote under his or her own name.  #4-6 will require other technologies.

Okay, which problems can be solved by having required voter ID?  Let’s assume, for the sake of discussion, we have a centralized state database keyed off the voter’s ID card number, but individual polling places do not have real-time access to this database.  Also, let’s assume that voter ID cards do not have any computational power: no smart cards, no crypto, etc.  #1 is ostensibly solved by the central database.  #2 cannot be prevented (at least, in a world with early voting or voting centers, where a voter has multiple places where he or she can legitimately vote), but it can be detected, and is thus disincentivized.  #3 is solved.  #4 is largely unsolved: if malicious poll workers want to forge signatures in the poll book, they may or may not be detected.  (In a recount situation, written signatures should be verified, but it’s unclear what the accuracy of that checking process might be.)

You could try to solve #4 with smartcards that issue digital signatures, but that’s a whole different can of worms.  Since the smartcard doesn’t really know what it’s being asked to sign, this could be exploited by an attacker.  (Example: you need to present your ID in a variety of different circumstances, such as proving your age to enter a bar.  The bouncer could “swipe” your card and use that as a way of getting a forged signature on an election record.)

What about #5 and #6?  These are really back-end database problems.  Requiring voters to present ID doesn’t have any impact.  However, having a database that is keyed off the voters’ ID cards significantly improves #5 and #6 and could ostensibly help reduce a variety of errors in the process.

Curiously, it seems that most of the benefit of requiring ID occurs in the back-end database, rather than on the day of the election.  The only real benefit of presenting ID, on election day, occurs in vote centers, early voting locations, and so forth.  When there may be millions of eligible voters who could use a vote center, traditional paper poll books are unworkable.  With a database keyed from ID card numbers, a voter’s records can be efficiently looked up and verified.  While this isn’t a security problem, improving the efficiency of the voting process is still a worthwhile goal.

Full post as published by Freedom to Tinker on April 29, 2008 (boomark / email).