There is another upside to relying on paper. Audits of such systems can require something else that, at first glance, seems like a hindrance: People need to show up to do them. As the “hanging chads” debacle in Florida demonstrated in the 2000 election, paper systems, too, can be badly designed. However, in a healthy democracy, requiring people to show up is a good thing.

There are already minefields ahead for this election. Georgia, for example, relies on electronic systems that leave no paper trail. The machines in Georgia are also quite old, and a Brennan Center for Justice report found that their software was “outdated” — primarily using operating systems like Windows 2000. This not only puts them at risk for crashes and lost votes, but also leaves them more vulnerable to hacking, as such older software no longer receives fixes for security flaws.

Since 1996, Georgia has voted for the Republican candidate in presidential elections, but this year a batch of recent polls have painted a tight race — with some polls even indicating that the Democratic nominee, Hillary Clinton, may have an edge. If the race is close, and the outcome questioned, voters in Georgia will have no means to audit the results. Other potential swing states, like Pennsylvania and North Carolina, also use electronic machines with no paper trail, at least in some counties. According to the nonprofit Verified Voting, people in at least a dozen states could encounter that same situation.

We have also seen concerns about foreign nations meddling directly in United States elections, via hacking or other means. This is an unlikely scenario; however, the fact that people are even voicing such concerns makes it all the more urgent to dispel them. As Matthew Green, a professor at Johns Hopkins University who specializes in cryptography and cybersecurity, said, “There is only one way to protect the voting system from a nation-state funded cyberattack: Use paper.”

Fortunately, there is a reliable and transparent method that combines convenience and the ability to perform an audit: paper ballot systems with optical scan counting. Avi Rubin, an expert on election security who is also a professor at Johns Hopkins, testified about a decade ago that when properly put into effect, these systems have many advantages. People can keep voting even if the equipment fails; it’s possible to audit results; and the systems are easy to use.

It is too late to fix everything for this election. But we should start planning to verify and audit voting wherever possible. For jurisdictions that still use electronic-only voting, we need to guard the machines, to avoid the kind of direct tampering that can turn them into Pac-Man consoles. Randomly selected units should also be used as “test only” machines on Election Day, to check that they are tallying the votes correctly.