The actual process of recording a vote sounds simple enough: a voter makes his or her choice, that choice is recorded, and then all the votes are tabulated to get a result. However, the electoral system is increasingly complicated and when you consider the millions of votes cast in the 2008 US Presidential election, there are many places where something could go awry. It also doesn't help that the mechanisms and regulations deployed in each state can be quite different from one another. They can even vary from county to county. Without a single unified system, this can create many problems.
Among other valid concerns, these are some of the reasons why any e-voting system needs to have a robust, transparent, and reliable system for audits. Better audits lead to more reliable results and a greater level of trust among the electorate. Further still, it is important to consider that the audits can and need to take place throughout the electoral process.
Even before the e-voting machines are deployed, they must be audited to ensure that they are reliable, keep secure records of the votes cast, record multiple instances of the voting information, maintain the confidentiality and integrity of voter ballots, and more. If the system is designed to automatically send the ballot information to central aggregators, the audits have to ensure that these transmissions are secure and free from tampering.
On Election Day, audits can take place to ensure the ballots are securely stored without compromising the secrecy of individual votes. The e-voting systems should also ensure that a voter can't vote twice and that a voter can't tamper with the machine. Many audits can also take place after the ballots are cast, possibly with paper trails to reconcile the multiple redundant instances of the vote information.
Going back to the 2008 election that eventually saw Barack Obama take office as the President of the United States, 150 votes were "dropped" from an e-voting machine during the primaries in Butler County, Ohio. Similarly, "vote flipping" was observed in early voting in West Virginia, Tennessee and other states. Voters selected a candidate, but saw their vote "flip" to another candidate. This was due to an improper calibration of the machines, something that could have been caught and fixed with a robust and thorough audit system.
Voter trust is very much at the center of the e-voting debate. Without trust, voters cannot feel comfortable using e-voting machines. They may be concerned about vote flipping, votes being dropped, or their privacy being compromised. Just as you want your bank's computing systems to be safe, secure, and audited, you want the same for casting your ballot in general elections. An automated e-voting system should have a voter verified paper trail with redundant backup copies that still maintain voter privacy.
The trouble is that auditing the electronic election technology is not required in most US states. Also, many systems keep no more than two recordings, leaving the possibility of lost data. The security and the encryption of these machines have also been brought into question. Again, this can come down to a robust and thorough audit system that includes a voter-verified paper trail, the recording of votes in multiple instances, and direct recording electronic voting machines that have been tested for reliability, accuracy, and security.