In this course, you'll learn what every citizen should know about the security risks--and future potential — of electronic voting and Internet voting. We'll take a look at the past, present, and future of election technologies and explore the various spaces intersected by voting, including computer security, human factors, public policy, and more.
Field Testing
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Securing Digital Democracy
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Security Procedures and Voting Around the World
Methods for ensuring the security of democracy
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J. Alex HaldermanAssociate Professor
Electrical Engineering and Computer Science
The last set of security procedures I want to talk about today have to do with ways
of testing voting machines on Election Day during the polling place, in the polling
place. Can we and can election officials
accurately detect if there is some kind of fraud going on in the machines.
So there's several elements of these kind of election day tests that are usually
written into election procedures. Some of them are basically legacy items
that come from the days of mechanical voting machines and even paper ballots.
One of these is the idea of the zero tape. So at the beginning of polling before any
votes are cast, a DRE voting machine will usually be made to print a tape indicating
that there are zero votes in it to begin with.
Now this could be helpful to detect procedural error if the officials somehow
forgot to reset the machine from the last election.
But it's not going to be very good at preventing fraudulent software,
vote-stealing software in the machine from operating.
Because the machine can just print whatever it wants.
Another kind of testing that we can have some more to say about is so called logic
and accuracy testing. Now this is an idea that comes from the
days of mechanical lever machines, and some of the procedures that were written
for those machines still survive in the era of DREs.
Logic and accuracy testing involves allowing people at the, at the polling place, poll
workers, or even candidates' representatives, to cast a number of votes
on the machine before real voting starts. So they'll have a miniature mock election
at the beginning. Now on a lever machine, this is a really
good idea. You wanna make sure that all those gear
mechanisms work, that they actually add a vote every time someone casts one for each
candidate, that they don't add more than one.
But on a DRE like the zero tape this can have almost, almost no effect in catching
actual vote stealing software. Vote stealing software would just
recognize that this is the logic and accuracy test, cuz it's a separate mode the
machines are put into. And it would just be programmed, the sensible
thing for any attacker, thinking like an attacker, is to program your fraudulent
software not to cheat during the logic and accuracy test.
So at best this could, could catch programming glitches.
It could cast errors in the ballot design, but it's not going to catch genuine fraud.
A third kind of test that is something that's been proposed but is not used
everywhere yet, is an idea called parallel testing.
And the idea here is that on election day we're going to take aside some machines
and conduct an election on them that's just not going to count.
So we're going to maybe randomly select a machine from a few precincts and on those
machines we're going to have some volunteers vote according to a script and
then at the end of the election day we'll print out the totals from those machines
and make sure that it matches the script. So before I talk about whether this is a
useful security procedure I want to give you a chance to think about it yourself.
If you were programming vote stealing software on machines that might
potentially undergo this sort of parallel testing, how would you still make it
cheat? What could go wrong?
So there's several ways that vote stealing software in a DRE might try to avoid being
caught in parallel testing. Even if the machine, some machines are
taken aside and carefully watched, where you know what the outcome should be after
people vote following a script. There are ways that vote stealing software
could avoid being detected. One way is that the vote-stealing software
could just try to differentiate between a real election and a scripted election.
Probably the simplest way to do that is to look at the total number of votes.
In a simplistic parallel testing regime, maybe you just have a few votes, 100
votes. Whereas in a real election, the machine
might be counting many hundreds of votes on Election Day.
So the vote-stealing software could just be programmed only to cheat after enough
votes were cast. A more sophisticated parallel testing
regime would have a script that had enough votes that it would be similar to a
realistic election. But sophisticated vote-stealing software
might still try to detect that it was a scripted action and not a real one.
Some things it could look for would be how long each voter took.
People who are following a script are going to get very quick at casting the
ballots. Whereas real voters are going to sometimes
take shorter time and sometimes longer. Another thing that the vote stealing
software could look for is errors that voters make.
Real voters are going to make errors, go back and correct them.
Perhaps people following a script are going to do it correctly with a higher
probability. So any kind of behavior that separates
rescripted voting from real voting is something vote stealing software can pick
up on and decide not to cheat if it thinks it's being tested.
Another kind of way that the vote stealing software could defeat parallel testing is
by using something called a secret knock. This is a signal that someone operating
the machine, say a user can send to the software by some sequence of action, say,
touching a particular place on the screen or even just voting a predetermine series
of choices. There are many ways to imagine making a
secret knock on the machine but there, there were couple of ways this kind of
triggering action could change its behaviour.
You might program your vote stealing software so that it only starts to cheat
if it receives a secret knock. So then you just have to have one person
one conspirator go and vote on each machine in order to enable the fraudulent
process. Another way is if you have conspirators
who are some of the testers there could be a secret knock to tell the machine not to
cheat. So this is potentially a more risky
strategy for the attacker but it's one that if you know your conspirators are
going to be there it would work. Another question about parallel testing
though that's probably a trickier one is what do you do if problems are found?
It's already election day. The votes have already been recorded on
the DREs. If there's no paper record, but you think
that some of them might have been tampered with, what can you do?
Those votes are already potentially lost and at least not able to be trusted.
So parallel testing is has its limitations.
It's possible that it would got, it would catch certain simplistic forms of frauds,
certain, poorly designed, attacks that didn't anticipated.
But it's not without, but it's not going to be any sort of guarantee that the voting
machines are, are behaving honestly. So we've talked about a lot of election
procedures today that are important for security and if these procedures aren't
followed correctly and if they're not followed exactly, that's going to create a
possibility for, for fraud to be committed or a potential for votes to be corrupted
or lost. But you have to remember that the people
who are charged with following these sometimes very complicated procedures are
election workers who are, are often volunteers or often given just a basic
amount of training and who only have to carry out these complicated instructions a
couple of times a year at most, on election days.
We know that people aren't great at following complex instructions to the
letter. So what are the odds that election
officials and election poll workers are going to make some mistakes? It seems like
it's just human nature. We've had some evidence of the rate of
error and the I can give you just a few data point on that.
It comes from a recent study, in which some computer scientists looked at the
electronic logs maintained by DRE voting machines in, fourteen counties from South
Carolina. And these logs noted different kinds of
events and they gave the researchers some insight into the rate of procedural error.
So, poll workers made quite a few mistakes across these counties.
About two percent of the machines from seven of those counties the researchers
found had never had their votes uploaded and so the votes weren't part of the final
count. People just forgot a crucial step in
tallying the votes. In some machines across seven of those
counties, there were other important errors.
The touchscreen displays weren't properly calibrated.
In eleven of those counties there were machines that had been opened and then
closed in an incorrect way. This is another possibility that
introduces potential security implications.
So the picture isn't very good. Some fraction of machines are going to
have procedural errors committed and the question is can we come up with sets of
procedures, sets of cross checks that are going to keep these rates to a minimum
because it's only human nature that some errors will occur.
When problems do occur whether they're the result of human error or just potentially
suspicious anomalies like a few broken seals, a few inconsistencies in review
screens or VD pad tapes, the question is will those problems be recorded, will they
be? Reported, will they be reviewed?
Will anyone notice if there's a pattern across a larger jurisdiction or state?
This is one of the last procedural component I want to mention but it's a
critically important one that there be some mechanisms in place for reporting and
explaining any kind of pattern of error that's happening.
First this is the only way that we'll be able to correct problems with the
procedures to debug that process requires some kind of widespread noticing and
correlating of problems. Second though problems that are low
probability but widespread are the best indicator that something's wrong with the
technology. If that, that might be the only way that
we have to observe that there's some bug or even some attempt at fraud happening
below the surface. If someone's building a piece of vote
stealing software. For instance, a virus that's spread to the
DREs across the state. They might have tested it to the best of
their ability, but not gotten it completely 100 percent right.
Maybe on a few machines, it's going to leave some kind of, it's gonna create some
kind of glitch, some kind of observable problem.
But the issue is, the problem is if no one is reporting, recording and correlating
reports of problems the chances are slim that anyone's ever going to notice that
something is wrong. This kind of vigilance is the price of
security especially with electronic voting machines.
And so it's critically important that election procedures have error tracking
and error reporting as part of, of the electoral process.
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