TRENTON - A trial to decide whether touch-screen voting machines are reliable or should be scrapped has been set for May, but the outcome almost certainly will be too late to change how millions of New Jerseyans vote in the presidential election.

Mercer County Superior Court Judge Linda Feinberg has been asked to decide whether the state's 10,000 electronic voting machines should still be used in elections, as the state contends, or whether New Jerseyans deserve a better system, as voting-rights advocates argue.

The court will conduct a full hearing on whether the electronic machines are scientifically reliable, Feinberg said while ruling on pretrial motions yesterday and setting a May 19 trial date.

However, as no decision is expected before September, New Jerseyans will vote electronically without a paper trail in November unless the governor or attorney general intervenes.

The Coalition for Peace Action and other plaintiffs have sued the state, trying to force a return to paper ballots that are counted by optical scanners. They claim electronic machines can be hacked into and have flaws that render vote tabulations unreliable.

"These machines are not safe to use and they shouldn't be used on Election Day," said Penny Venetis, a lawyer at the Rutgers Constitutional Litigation Clinic who represents the plaintiffs.

The state has been trying for at least three years to lessen concerns by retrofitting the machines with printers that produce paper receipts that voters could see but not take home.

The Attorney General's Office, which oversees elections in New Jersey, is about to miss the second deadline set by the Legislature to have the paper-balloting safeguard in effect. The Assembly and Senate have approved a measure extending the deadline to January 2009.

Gov. Corzine is expected to sign the bill, said his spokeswoman.

Venetis said at least 20 states had banned touch-screen voting machines similar to those in New Jersey.

She cited New Mexico as one example, saying Gov. Bill Richardson scrapped electronic voting after the machines proved unreliable. She said that state made the transition in seven months to optical scanners that count paper ballots.

Venetis won a victory in court yesterday when Feinberg ordered her to have access to the Sequoia Voting Systems machines that clerks in six counties reported problems with during the Feb. 5 presidential primary.

The clerks discovered one- or two-vote discrepancies between the number of votes recorded on computer cartridges versus those on the paper-tape backups.

Venetis wants computer scientists at Princeton University to test the machines, but the manufacturer previously resisted the request, threatening litigation.

On Tuesday, lawyers for the state said they didn't know whether New Jersey had a confidentiality agreement with Sequoia preventing the tests, so Feinberg ordered the testing to proceed.

The spokeswoman for Sequoia, Michelle Shafer, was not available for comment yesterday. In an e-mail sent last week, she said that Sequoia was committed to maintaining voter confidence and that all company products were reviewed and tested by the federal Election Assistance Commission.