SAN DIEGO -- County supervisors today could ask the state to toughen election laws by requiring people to show proof that they are U.S. citizens when they register to vote and identification at the polls before being allowed to vote.

Under current law, people are not required to show proof of citizenship, and only first-time voters who register by mail are required to show identification -- which does not have to include a photograph -- at the polls.

Supervisor Bill Horn, who recommended the Board of Supervisors petition the state to change state voting laws, said having to show birth certificates or passports when registering and photographic identification at the polls would prevent voter fraud.

However, some civil rights groups said the proposed changes could intimidate some voters and drive down voter registration and participation, which state officials say is among the lowest in the country.

Today, supervisors will specifically consider passing a resolution supporting the Federal Election Integrity Act of 2004 and sending a letter to California Secretary of State Kevin Shelley pushing for tougher registration requirements.

The federal bill, sponsored by U.S. Rep. Henry Hyde, R-Ill., and 21 other U.S. representatives, calls for the same identification requirement changes for federal elections, but not state elections, and is currently in the House Administration Committee.

County Registrar Sally McPherson said Monday that because current law does not require proof of citizenship, people registering to vote are simply asked to check a box, "under penalty of perjury," testifying that they are U.S. citizens. But McPherson said election officials do not check to verify citizenship.

Horn said asking each potential voter to show an identification card that includes a photograph should not be looked upon as a burden.

"I don't think that's too much of an imposition," Horn said. "When you go down to the local store and rent a video you have to show an ID. Voting, to me, is a lot more important than cashing a check."

Officials from the Republican Party of San Diego County also said they felt the changes were "reasonable." San Diego County Democratic Party officials said Monday that they had no position on the issue.

However, Nancy Sasaki, executive director of the American Civil Liberties Union, said the proposed changes could intimidate some minority voters who fear "racial profiling" and older voters who no longer have identification such as driver licenses. She said those fears could keep them from voting.

"You could create doubt in people's minds if they would be acceptable," Sasaki said, "and they could think, 'Well, why should I even bother to hassle with another bureaucracy?' "

Steve Blackledge of the California Public Research Interest Group said the changes could also hurt voter registration.

"It's just another barrier in terms of voting," he said. "We should be doing more to encourage people to vote."

Contact staff writer Gig Conaughton at (760) 739-6696 or gconaughton@nctimes.com