Why Audit Election Results?
No voting system is perfect. Nearly all US elections today are counted using electronic voting systems. Such voting systems have produced result-changing errors through problems with hardware, software, and procedures. Errors can also occur in hand counting of ballots or in the compiling of results. Even serious error can go undetected if results are not audited effectively.
Well-designed and properly performed post-election audits can significantly mitigate the threat of error, and should be considered integral to any vote counting system. A post-election audit in this document refers to hand-counting votes on paper records and comparing those counts to the corresponding vote counts originally reported, as a check on the accuracy of election results, and resolving discrepancies using accurate hand counts of the paper records as the benchmark. Such audits are arguably the most economical component of a quality voting system, adding a very small cost for a large set of benefits.
The benefits of such audits include:
- Revealing when recounts are necessary to verify election outcomes
- Finding error whether accidental or intentional
- Deterring fraud
- Providing for continuous improvement in the conduct of elections
- Promoting public confidence in elections
Post-election audits differ from recounts. Post-election audits routinely check voting system performance in contests, regardless of how close margins of victory appear to be. Recounts repeat ballot counting in special circumstances, such as when preliminary results show a close margin of victory. Post-election audits that detect errors can lead to a full recount. When an audited contest is also recounted, duplicate work can be avoided (see Best Practices 9a).
Voting systems should have reliable audit records. Best effort audits should be performed even if the technology does not support optimal audits, or even if the laws do not permit optimal remedies. No single model for post-election audits is best for all states. Election traditions, laws, administrative structure and voting systems vary widely. Nonetheless, there are guiding principles that apply across all states. As states develop their own audit models, the public should have the opportunity to help shape those regulations.
 For example, in Pottawattamie County, Iowa, in the June 2006 primary election for County Recorder, the original optical scan count showed challenger Oscar Duran defeating the incumbent, John Sciortino. A hand count showed that Sciortino actually had won handily; the scanners had been misprogrammed. In Napa County, California, after the March 2004 primary, the 1% manual tally discovered that the optical scanners had been miscalibrated and were failing to detect the dye-based ink commonly used in gel pens. The ensuing recount recovered almost 6700 votes (but no outcomes changed).
 For instance, in Minnesota after the 2006 general election, the cost of the wages for election judges (pollworkers) to count votes has been estimated at $24,500 to $27,000 statewide – 9 to 10 cents per hand-counted vote, and about 1.2 cents per voter in the election (http://www.ceimn.org/files/CEIMNAuditReport2006.pdf). While audit costs will vary depending on the scope of the audits and other considerations, they can be expected to be a small fraction of election administration costs.
 We will use “contest” to refer to any ballot item (such as an election to public office or a ballot initiative) – not to a challenge to the results, as in some states.
 The proposal of best practices for auditing a given system does not imply an endorsement of the system.