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Once voters have cast their ballots in an election, that’s usually the end of the story for them. But for election officials, things are far from over.
In the coming days, county and state officials around the country will start double-checking election results to make sure they are accurate.
Concerns about the accuracy of election results have proliferated in recent years amid allegations of fraud and vote-switching. But post-election audits of the results are a routine part of every election and aim to increase confidence that every vote has been correctly recorded.
Here is everything you need to know about how officials verify election results.
What is a post-election audit?
A post-election audit is a test to make sure that voting equipment was functioning properly on Election Day or that the correct procedures were followed. While election officials run logic and accuracy tests before Election Day to prove to the public that voting equipment is functioning properly, post-election audits are the flip side of that coin, proving that the vote counts are accurate.
The exact process varies from state to state, but it generally involves taking a certain number of ballots and recounting them — either on different equipment or sometimes by hand — and comparing those results with the original results recorded by the tabulators used on Election Day.
Luke Belant, project manager for elections and redistricting at the National Conference of State Legislatures, said audits are meant to verify results, detect issues, and give voters and other stakeholders confidence in the process.
“It is essentially, to my knowledge, unheard of for outcomes to be altered,” he said. While small changes do sometimes happen, because a machine may interpret a mark on paper differently than a human, “modern voting systems are highly reliable, so results are routinely affirmed.”
What types of audits take place?
There are two main types of audits: a traditional audit and a risk-limiting audit.
Generally speaking, a traditional audit requires that election officials recount a set number of ballots or voting precincts. But each state does it a little differently.
For example, Alaska requires that officials take one precinct from each U.S. House district that accounts for at least 5% of the ballots cast in that district. If the audit finds a discrepancy of 1% or more from the reported results, election officials must hand-count all the ballots in the precinct.
In Montana, officials must audit 10% of the precincts in a county or at least two precincts. If any discrepancies are found, the voting machine used on Election Day cannot be used again until it is examined, and at least three more precincts must be audited.
The second type of audit is a risk-limiting audit. Rather than looking at a specific district or batch of ballots, a risk-limiting audit recounts a random sample of ballots from across the election.
How many ballots get audited depends on how close the margin of the election was. If the election was won by a wide margin, fewer ballots are recounted. If the margin was close, more ballots need to be recounted.
Ben Adida, the executive director of VotingWorks, an election technology company that provides software for risk-limiting audits, said those audits are viewed as “the gold standard.” He said they can be thought of as similar to exit polling, where a sample of voters leaving the polling place are asked who they voted for.
“If you ask enough of them, you get a statistically significant idea of how voters voted,” he said.
Some states also conduct procedural audits to check for things like whether voter registration rules were followed properly.
What states do post-election audits?
Every single state in the country has some type of post-election audit procedure, according to the National Conference of State Legislatures. Some states, such as Pennsylvania, even do two audits.
Most states require the audit be conducted before the results are certified, but 10 states do them after certification, and nine others don’t specify.
According to the NCSL, 36 states and the District of Columbia do traditional post-election audits. Seven states conduct risk-limiting audits. The remaining states use some other kind of audit, such as a procedural audit, that does not fit into those two categories or is conducted on a less strict basis.
Carter Walker is a reporter for Votebeat in partnership with Spotlight PA. Contact Carter at cwalker@votebeat.org.
