Discussion
Election nerditry: Mississippi is getting a lot of attention, with it's razor-thin margin in the still-not-yet-fully-counted Senate contest and lack of a recount provision in its election law. Whoever wins, the loser is virtually guaranteed to feel unsatisfied by a process that denies them a safeguard that's available in some form in every other state.
This may serve as the catalyst for MS to add a recount trigger to its election law, but I think that would represent a missed opportunity.
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That is, recounts assume that any errors in the tally will be fairly small. The precise margin that triggers a recount varies from state to state, but almost every state recount rule is based on this assumption.
But modern automated ballot tally systems are vulnerable to different kinds of errors than those committed by fatigued (or perhaps even dishonest) human counters. Current systems might make small errors, but they can also fail much more catastrophically.
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Modern tally systems, such as optical-scan ballot readers, are controlled by software. Software is notoriously unreliable and subject to unexpected bugs, even after rigorous testing, and the software used in ballot tally systems has proven to be no exception. But worse, software is designed to be *replaceable*, which means that it may be possible for an adversary to replace the tally software with malware that reports any result the attacker desires, and then erases its tracks.
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Fotunately, there's a reliable, rigorous, and efficient safeguard against tally system errors and malway, and it works for any voting system that has reliable paper ballots. It was invented about 20 years ago by Berkeley statistician Phillip Stark. The method is called "Risk Limiting Audits" (RLAs), and is regarded as the gold standard for protecting elections against tabulation errors or malice.
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In a Risk-Limiting Audit, a random sample of ballots is compared (by human judges) with how the automated tally system interpreted them. As you sample more ballots that were interpreted correctly, you gain more confidence that the automated system reported the correct overall outcome. Some relatively straightforward statistical math lets us quantify the level of confidence we achieve (called the "risk limit") and when we can stop sampling.
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@mattblaze who picks the judges though?
@mattblaze great opportunity to implement ranked choice voting!
"Recounts", as implemented in almost every state, were designed as a safeguard against small-scale human error, dating from the days when ballots were hand counted (sometimes by candlelight) on election night. It was natural to expect that people would make mistakes.
So recounts are generally triggered when the margin of victory is within the expected margin for error of the counting process that existed at the time the law was enacted.
The assumptions here are obsolete.
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