Washington residents have been jittery about ballot integrity since at least the 2004 election with its multiple recounts, court intervention and the narrowest gubernatorial election in U.S. history. Suspicion of underhandedness lingers in some minds more than two years after Gov. Chris Gregoire took office.

Now, despite considerable recent effort to make elections in Washington as clean as possible, the Legislature is actually considering a proposal that would make it harder and more expensive to eliminate fraud and error.

Senate Bill 5561 would allow citizens to register to vote up to and on election day, forcing elections workers to undertake the checking and double-checking of new registrations even as they are swamped with chores to prepare for an upcoming vote.

Current law gives the workers 15 days to wrap up the first set of demands while transitioning to the next. If the pending bill becomes law, county auditors would have to hire extra help to get through the chaos.

A fiscal note prepared for the House of Representatives estimates the measure would cost the Secretary of State’s Office more than $1.3 million a biennium. The 39 counties would face another $6.3 million collectively in added costs.

Eight million bucks is a hefty price tag just to spare late-registering voters the consequences of their own procrastination. Accomplishing election-day registration would force Spokane County alone to divert an estimated $137,709 from other important services.

As it is, unregistered voters who want to go on Washington’s rolls can sign up at any time, even just before an election. But the applications submitted in those last 15 days now can be processed after the impending election and its demanding aftermath. Under the proposed bill, that flexibility would vanish.

Last-minute registrations are no trivial matter. In Idaho and other states that allow election-day registration, an average 10 percent to 20 percent of the voters avail themselves of it. That’s a recipe for mayhem.

In Minnesota, where the demographics and population distribution are similar to Washington’s, almost 600,000 election-day registrations were processed in 2004. Wisconsin had more than 400,000 in 2006. It’s estimated that Spokane County would have some 43,200 in 2008.

States like Minnesota and Wisconsin can get away with the procedural traffic jam, because they let voters cast their ballots before confirming that they’re valid. Washington law, on the other hand, requires officials to take all the steps aimed at preventing ineligible participation before the ballot is cast. Washington’s approach is more comforting.

But just picture the day 43,200 impatient would-be voters line up at the auditor’s counter expecting to register, vote and then go home whistling a patriotic tune. Is it any wonder the state auditors’ association and Secretary of State Sam Reed are united against the proposal?

Lawmakers who want to increase the percentage of eligible citizens who register to vote have a grand idea, but they need to set this flawed approach aside and consult with state and county elections officials to work out a way to manage it without inviting catastrophe.