End-to-End Verifiability Key to Future Election Security

In the days following the election, President Trump and his surrogates made allegations of widespread voter fraud, claiming this was the reason he lost his campaign for re-election. And Trump’s team was not the only one claiming malfeasance at the polls — multiple candidates across the country who lost decisively still refused to concede their races on the grounds that they were victims of election fraud. Though unsubstantiated, these claims had an impact on voters: A week before the election, 68 percent of Republicans reported that they trusted U.S. elections “a lot” or “some,” on par with Democrats, but a week after the election, following an endless stream of accusations of election fraud, trust in U.S. elections among Republicans had dropped to 34 percent.

While there is no evidence to support the notion that voters or election officials have tampered with the results, this does not mean that conversations about how to make elections more secure should be off the table. On the contrary, as state and local election officials look toward future elections that may similarly be marked with voters deeply divided along partisan lines, it will be more important than ever for them to strengthen election security so that voters have confidence in election results.  

Many states have already made some progress in recent years. Previously, most voters could not check whether election officials had received their mail-in ballots. As of the 2020 presidential election, 45 states and the District of Columbia had some form of mail-in ballot tracking, so voters could see if (and when) their local election office had sent or received their absentee ballots.  

The problem for voters is that ballot tracking only solves part of the problem. Voters may still question whether anyone has tampered with their ballots, whether anyone has stuffed the ballot box and whether the ballots have been correctly tallied. To be clear, election officials have multiple processes and procedures in place to mitigate these threats, such as physical security controls to prevent election officials from introducing fraudulent ballots, election observers to witness any ballot tampering and post-election audits to uncover any tabulation errors. But voters who distrust the system need more.

One solution to this problem is to introduce end-to-end (E2E) verifiability in elections. E2E allows voters to know that not only have election officials received their ballot, but also that no one has tampered with it along the way. E2E makes this possible by creating a unique tracking number that is cryptographically linked to how they cast their vote, ensuring that any attempt to alter their ballot could be detected.  

Moreover, E2E allows everyone — news media, political parties, candidates, voters and outside observers — to fully audit the results of an election, ensuring that all ballots are counted as cast, while still protecting voters’ privacy. E2E enables this feature using homomorphic encryption — a special type of encryption that allows people to perform certain mathematical operations, such as addition, on encrypted data without first decrypting it.  

Perhaps the best part of E2E is that it is a concept, not a single product, and multiple companies, researchers and election officials have devised E2E voting systems. And some even have substantial backing — Microsoft, for example, released a free, open source software development kit that developers can use to integrate E2E into their voting systems.  

Trust in elections is crucial to a healthy democracy. As election officials know, the purpose of elections isn’t to convince people who won, but who lost. E2E is not a silver bullet, and conspiracy theories and misinformation may still take hold among some segments of society no matter how free and fair an election may be. But this should not deter state and local officials from continuing to innovate in elections to make them more secure and trustworthy.