It would be a terrible injustice if absentee ballots cast by military personnel and Americans living overseas were rejected because those voters had trouble deciphering the convoluted federal and state rules for filling out the forms.

Attorney General Bob McDonnell instructed local registrars this week to count overseas absentee ballots even if they lack the addresses of the corroborating witnesses, as required by state law.

McDonnell argued in his legal opinion that federal law, which does not require the address of the witness, takes precedence over the state statute. While the immediate effect of his ruling is positive, it leaves city and county registrars in the delicate position of ignoring a state law. More troubling, registrars may have added difficulty verifying the authenticity of the ballots if they are challenged.

The number of votes at stake is small - about 125 statewide. Only a fraction of those are members of the military stationed overseas.

But much larger principles are at stake, and both congressional and state leaders should take quick action to ensure that the confusion is resolved before the next federal election.

Congress and Virginia's General Assembly have adopted reforms in recent years intended to make voting as easy as possible for soldiers, sailors and civilian Americans who must deal with infrequent military mail transmissions or undependable foreign postal systems. One option permits them to apply for an absentee ballot and cast their vote in a single step.

In approving that shortcut for Virginia, state lawmakers gave voters until five days before the election to get the ballot to their local registrar. Because of the tight time-frame, state law requires not only the voter's address but also the address of a witness for verification. Federal rules require the voter's address but only the witness' signature, while setting a much earlier application deadline of 30 days before the election.

McDonnell's opinion describes the tortuous instructions posted on the Web site of the Federal Voting Assistance Program, an agency responsible for voter education efforts. The thicket of drop-down menus, computer links and bureaucratic babble would likely stymie Bill Gates and U.S. Chief Justice John Roberts, much less a Marine stationed in Afghanistan.

Federal and state officials must find the proper balance between the competing goals of encouraging democratic participation and preventing fraud.

There is no evidence of fraudulent overseas votes in Virginia, but squishy and conflicting rules are an invitation for mischief.

Uniform federal standards for overseas absentee ballots, not to mention a better Web site, would be welcome reforms. But state officials can't ignore the problem and wait for a solution from Washington, D.C. They must determine whether the additional information required by state law is necessary to prevent fraud or whether those requirements can be stricken.

Trust is an inherent part of every election, and next week's election is no exception. But clarity is also crucial, and existing rules fall too far short of that standard.