It was ripe for a challenge.

A constitutional amendment that voters overwhelmingly approved in 1998 was meant to open access to primaries to all voters, regardless of political affiliation, if there was no opposing party candidate in the general election. Year after year, partisans in Tallahassee had blocked such a law — until voters spoke up.

Then came a lamebrain opinion by then-Secretary of State Katherine Harris in 2000. In response to a request by Marion County officials, Ms. Harris effectively shut down Florida voters’ constitutional right to vote when there’s a write-in candidate on the ballot.

Yet write-in candidates aren’t held to the same standards as those running with a party label. Write-ins don’t have to pay a filing fee or collect signatures but simply apply to a county supervisor of elections to provide a blank space on the ballot. The write-in candidate’s name won’t appear on the ballot — putting the onus on voters to “write in” the candidate’s name.

In effect, the write-ins have become a poison pill to close primaries and disenfranchise most voters in a city or county or district.

Both parties have abused the write-in rule statewide. Before Ms. Harris’ opinion, there were only three instances since 1978 in which the winner of a primary faced only write-in candidates in the general election. But from 2000 to 2010 there were 58 such instances — a whopping 1,800-percent increase.

Now there’s a legal challenge to the write-in shenanigans involving the Miami-Dade state attorney’s race. State Attorney Katherine Fernandez Rundle has a Democratic Party opponent, Rod Vereen. But because there are two other candidates — write-in spoilers who have been AWOL from the political process — the Aug. 14 primary election will be decided only by 525,890 Democrats. This shuts out some 700,000 county voters, about half of them either Republicans or independents.

In effect, the state attorney’s race will be decided by only 43 percent of the county’s registered voters. That’s plain wrong.

In fact, the Democrats’ statewide chairman, Rod Smith, makes clear in an affidavit filed in the federal lawsuit that the party has “no official rule or position” and “it does not assert any First Amendment interest” for closing the state attorney’s race.

Two county voters — one a Republican, the other independent — filed the federal lawsuit against the county elections supervisor on June 29.√. They argue that minutes from meetings by the Florida Constitution√ Revision Commission, which put the open primary amendment on the √1998 ballot, show the intent was to open all primaries when there were no opposing-party candidates, period.

The state attorney’s post is too important to leave out 57 percent of county voters.

A hearing is set for July 12, but primary ballots have already been printed. Still, there’s a way to proceed with an open race while waiting for a ruling and any appeals.

Because the local elections supervisor, Penelope Townsley, is appointed by the county mayor under the home-rule charter, Mayor Carlos Gimenez has some latitude to open the race to all voters. He could order that general election bal lots include the state attorney’s race and that the results of the Aug. 14 primary be sealed or not tabulated until the case is settled in court. This should not cost county taxpayers one extra cent.

Mr. Gimenez, facing his own election challenge to the nonpartisan mayor’s seat, should ensure that all county voters get to pick their state attorney just as they will get to choose their mayor.