Congress has stood idly by while states have done the hard work of trying to make electronic voting more reliable. Now the Senate is taking up a dangerous bill introduced by Senators Dianne Feinstein, Democrat of California, and Robert Bennett, Republican of Utah, that would make things worse in the name of reform. If Congress will not pass a strong bill, it should apply the medical maxim: first, do no harm.

Voters cannot trust the totals reported by electronic voting machines; they are too prone to glitches and too easy to hack. In the last few years, concerned citizens have persuaded states to pass bills requiring electronic voting machines to use paper ballots or produce voter-verifiable paper records of every vote. More than half of the states now have such laws.

There is still a need for a federal law, so voting is reliable in every state. A good law would require that every vote in a federal election produce a voter-verifiable paper record, and it would mandate that the paper records be the official ballots. It would impose careful standards for how these paper ballots must be “audited,” to verify that the tallies on the electronic machines are correct.

The Feinstein-Bennett bill does none of these. It would permit states to verify electronic voting machines’ results using electronic records rather than paper. Verifying by electronic records  having one piece of software attest that another piece of software is honest  is not verifying at all. The bill is also vague about rules for audits, leaving considerable room for mischief. The timeline also is unacceptable. States might be able to use unreliable machines through 2014 or longer.