Recent articles on voting:

Evidence-Based Elections: Create a Meaningful Paper Trail, then Audit, by Andrew W. Appel and Philip B. Stark, Georgetown Law Technology Review, volume 4, pages 523-541, 2020.

Ballot-Marking Devices Cannot Assure the Will of the Voters, by Andrew W. Appel, Richard A. DeMillo, and Philip B. Stark. Election Law Journal, to appear 2020. (Non-paywall version, differs in formatting and pagination; earlier versions appeared on SSRN.)

Are voting-machine modems truly divorced from the Internet?

Securing the Vote — National Academies report

Serious design flaw in ESS ExpressVote touchscreen: “permission to cheat”

Design flaw in Dominion ImageCast Evolution voting machine

Continuous-roll VVPAT under glass: an idea whose time has passed

An unverifiability principle for voting machines

Ten ways to make voting machines cheat with plausible deniability

Cheating with paper ballots

End-to-End Verifiable Elections

When the optical scanners jam up, what then?

Two cheers for limited democracy in New Jersey

Florida is the Florida of ballot-design mistakes

Expert opinions on in-person voting machines and vote-by-mail

Why voters should mark ballots by hand

Pilots of risk-limiting election audits in California and Virginia

Reexamination of an all-in-one voting machine

Voting machines I recommend

BMDs are not meaningfully auditable

ImageCast Evolution voting machine: Mitigations, misleadings, and misunderstandings

How to do a Risk-Limiting Audit

Five-part series on ballot-level comparison audits:

TEDx talk, March 2016

Teaching

My introductory lecture for the Debate on Internet Voting sponsored by the Overseas Vote Foundation, March 19, 2010.

My Freshman Seminar course "Election Machinery" on election administration and voting technology, Fall 2008

My Freshman Seminar course "Election Machinery" on election administration and voting technology, Fall 2004

Research and Public Service

New Jersey Election Cover-up: During the June 2011 New Jersey primary election, something went wrong in Cumberland County, which uses Sequoia AVC Advantage direct-recording electronic voting computers. I served as an expert witness in the resulting lawsuit. From this I learned several things; see the attached report.

New Jersey court-ordered election-security measures have not been effectively implemented. There is a reason to believe that New Jersey election officials have destroyed evidence in a pending court case, perhaps to cover up the noncompliance with these measures or to cover up irregularities in this election. There is enough evidence of a cover-up that a Superior Court judge has referred the matter to the State prosecutor's office. Like any DRE voting machine, the AVC Advantage is vulnerable to software-based vote stealing by replacing the internal vote-counting firmware. That kind of fraud probably did not occur in this case. But even without replacing the internal firmware, the AVC Advantage voting machine is vulnerable to the accidental or deliberate swapping of vote-totals between candidates. It is clear that the machine misreported votes in this election, and both technical and procedural safeguards proved ineffective to fully correct the error.

Security Seals On Voting Machines: A Case Study, by Andrew W. Appel. Accepted for publication, ACM Transactions on Information and System Security (TISSEC), 2011.

Abstract: Tamper-evident seals are used by many states' election officials on voting machines and ballot boxes, either to protect the computer and software from fraudulent modification or to protect paper ballots from fraudulent substitution or stuffing. Physical tamper-indicating seals can usually be easily defeated, given they way they are typically made and used; and the effectiveness of seals depends on the protocol for their application and inspection. The legitimacy of our elections may therefore depend on whether a particular state's use of seals is effective to prevent, deter, or detect election fraud. This paper is a case study of the use of seals on voting machines by the State of New Jersey. I conclude that New Jersey's protocols for the use of tamper-evident seals have been not at all effective. I conclude with a discussion of the more general problem of seals in democratic elections.

Analysis of the AVC Advantage DRE voting machine: In July 2008 I led a team of computer scientists in a study of the software and hardware of the Sequoia AVC Advantage. This is in connection with the NJ voting-machines lawsuit.

Summary article:

The New Jersey Voting-machine Lawsuit and the AVC Advantage DRE Voting Machine, by Andrew W. Appel, Maia Ginsburg, Harri Hursti, Brian W. Kernighan, Christopher D. Richards, Gang Tan, and Penny Venetis.

Published in EVT/WOTE'09, Electronic Voting Technology Workshop / Workshop on Trustworthy Elections, August 2009.

Technical reports: