Two voters whose native language is not English yesterday filed a federal lawsuit challenging the legality of next month's special congressional election.

The suit claims that the state's preparations for next month's mail-in election violate laws protecting voters who have limited proficiency in the English language.

The suit was filed by attorney Eric Seitz on behalf of two registered voters, De Guang Chen and Yong Tang Xie, "who speak Chinese and have limited proficiencies with the English language," the lawsuit states.

The suit alleges that the mail-in ballots to be sent to registered voters by the state Office of Elections will be only in English and that voters will separately receive "abbreviated" multilingual instructional materials.

"Facsimile ballots" which can be requested from the state also will be only in English, as will the instructions on how to fax the completed ballots to the Office of Elections, the suit alleges.

Absentee ballots in Chinese, Japanese and Ilocano will be available to voters, but instructions on how to obtain them are written only in English, according to the suit.

The state Attorney General's Office issued a statement last night that "the Office of Elections believes it is in compliance with federal law with respect to limited English proficiency voters, and that the lawsuit lacks merit."

The elections office is taking steps to help speakers of Japanese, Chinese and Ilocano who have limited English proficiency, the statement said.

Steps include placing ads on foreign-language radio stations, using those languages on voter registration forms, encouraging people to call the Aloha United Way 211 hotline (whose operators will be prepared to offer help in this area) and offering help at the walk-in voting site at Honolulu Hale.

Seitz cited census data that show that 5 percent of eligible voters in Honolulu and Maui counties are members of "single language minority groups" who "do not speak or understand English well enough to participate in the election process."

The state is required by federal law to provide bilingual ballots in Honolulu County in the Chinese, Japanese and Ilocano languages and in Ilocano in Maui County, the suit alleged.

The lawsuit seeks an injunction requiring the state to remedy the alleged deficiencies in its special election plans.

The election is to fill the U.S. 1st Congressional District vacancy created when Rep. Neil Abercrombie resigned to run for governor.

Mail-in voting is scheduled to begin May 10 and to be completed May 22.