Voter anonymity, also known as the secret ballot, is a cornerstone of modern democracy.
On a blockchain, voter anonymity is protected because, in fact, the keys described above are paired. Each pair consists of both a public key and a private key. The public key will tell anyone who looks at the blockchain that, for example “voter number 2,967,349,509,681 voted at X time.” The private key, known only to the individual voter, tells her she is voter number 2,967,349,509,681. The rest of the transaction record, or block, indicates that this vote was cast for outcome Y. The resulting anonymity is of paramount importance, to prevent coercion.
Yet it’s important to acknowledge that no voting system can ever perfectly protect the values of voter anonymity, vote verifiability, and election system integrity all at once; tradeoffs are inevitable. For example, the most secure low-tech alternative, a paper ballot, is vulnerable to theft and destruction; reliable hand-counts are unlikely to scale globally: there are simply too many opportunities for human malfeasance.
It’s also important to consider whether we gain anything at a systemic level if we insist on perfect anonymity at the expense of verifiability and system integrity. Election results can be — and have been — called into question, and without an immutable record such as a blockchain, a voter has no way to know if her vote was properly counted.
Although there have been cases where the anonymity of blockchain private keys has been compromised, cracking them is resource intensive, especially at scale. In addition, anonymity protection is an active frontier of blockchain development, led by platforms such as Zcash, which claim to fully protect user anonymity.
Robust anonymity, though imperfect, is at the core of blockchain design. With ongoing development, and considering the tradeoffs, we believe it’s strong enough to rely on.
Unique identity is also critical to any voting system, akin to voter registration, or a driver’s license or passport, to ensure that each person has exactly one voting account. This too is an active focus of development, led by platforms such as Blockstack.
There is a design challenge in how best to ensure that new identities are authentic and unique. Here too, no system is perfect — witness forgeries of passports and other paper-based identification systems.
A promising design is for each new person to digitally record a short facial video self-portrait, label it with her claimed identity, e.g. “Jane P. Smith, born July 18, 1999 in Stockton, CA, USA”, and upload it to a blockchain, where other people who know her (and whose identities are already blockchain-verified) confirm, “Yes, this is Jane P. Smith”. This leverages crowdsourcing for authentication, in a way that finer-grained biometrics such as retinal scanning, DNA testing or fingerprinting can not, because those measures are not easily readable to most people, while faces certainly are. In addition, moving video offers added security against spoofing, in comparison to still portraits.
Scaling, or ensuring adequate computational power to record votes by billions of people on a blockchain, is a non-trivial challenge. This too is an ongoing, active development frontier. And as Moore’s Law notes, computing power tends to double every two years. Quantum computing will help. (Although limits to Moore’s law have recently been predicted, so far technology has always continued to advance.)
Digital divide: A democracy is only global if everyone on Earth can access it. We must close the digital divide. While there’s a long way to go, major technology companies are investing heavily in the race to connect the world’s population to the internet. Measured geographically, the divide is closing steadily, even before these investments bear fruit. Demographic statistics showing that internet usage correlates with youth also suggest that the inexorable transition of generations will help close the digital divide.
Considering all of this, it seems likely that the digital divide will be essentially closed within 10 to 20 years, perhaps sooner.
In summary, blockchains can now provide the necessary technological platform to securely support a global democracy. As the digital divide closes, our system can be ready to include everyone.