On March 27 and 28, 2010, Verified Voting and Common Cause sponsored a meeting of in Washington, D.C. to share experiences and ideas for improving post-election audits. The participants included election officials, statisticians, computer and political scientists, election integrity advocates, and voting system vendor technical staff. This meeting marked the first time that diverse stakeholders, including voting systems vendors, met together for the explicit purpose of identifying the potential benefits and challenges of using small batches of ballots (i.e., smaller than precincts — down to and including individual ballot records) to make audits more effective and efficient.
Currently, hand-counting a sample of entire election precincts is the most common method of post-election manual auditing. To check the accuracy of electronic vote tallies, states that allow audits typically choose a specific number or percentage, of precincts to audit. Then, ballots in the selected precincts are hand counted. Finally, the results are compared with the official reported tallies produced by an electronic voting system.
However, auditing entire precincts often results in hand counting many more ballots than may actually be needed to confirm the outcomes of an election (in general elections, 1000 or more ballots per precinct is common). Experts have recognized the potential of “Small Batch Auditing” – auditing methods that use smaller units than entire precincts – to increase the efficiency of election audits (further discussion of these methods can be found here).
Meeting participants agreed on a wide number of points, including:
- It must be easy to obtain vote subtotals smaller than entire precincts from voting systems..
- It must be easy to obtain the physical ballots to which those subtotals correspond.
- Voting systems components should support a standard data format to facilitate auditing and data exchange.
- Accuracy of hand counts is essential, since that is the independent standard against which the electronic vote tabulation is compared.