PASADENA -- A federal appeals panel cast doubts Thursday on California's plan to hold next month's recall election because almost half the voters would be using error-prone punch-card ballots.

The three judges voiced even deeper reservations about allowing an Oct. 7 vote on another ballot question -- the racially charged Proposition 54 -- while the odds of casting an invalid ballot are almost tripled in Sacramento, Los Angeles and four other counties that still use punch-card voting machines.

The voters may have a strong interest in deciding the fate of Gov. Gray Davis immediately, the 9th U.S. Circuit Court of Appeals panel said. But no matter when Proposition 54, which would bar most state collection of racial data, is on the ballot, the effective date would be 2005.

The 9th Circuit ranks one step below the U.S. Supreme Court, where the case is almost certainly headed. It probably will be the last to be resolved of close to a dozen legal challenges to the Oct. 7 election.

References to Florida's 2000 presidential election debacle and Bush v. Gore, the Supreme Court decision that ended it, were numerous during almost two hours of spirited oral arguments.

Punch-card machines have "a number of problems you can't design out" by voter education or any other fix, said Judge Sidney Thomas of Billings, Mont.

Nothing, said Thomas, can ensure that voters won't destroy their ballots by picking more than one candidate for governor or that chads won't hang or become pressed back into a ballot card -- all problems that were experienced in Florida three years ago.

The lawsuit contends that 40,000 Californians, many of them minorities, will be disenfranchised because of such ballot defects.

The constitutional question, the judges said, is what level of disparity in the reliability of different voting systems should cause a federal court to put its foot down.

The judges gave no indication of when they will rule.

But after facing a barrage of critical questions, Douglas Woods, the deputy attorney general who presented the state's case, requested a stay of the forthcoming order, if he loses, so that election preparations can continue during a Supreme Court appeal.

Woods argued that civil rights groups signed off in 2002 on an agreement to decertify California's punch-card machines as of the March 2004 primary election. By doing so, he said, they relinquished the right to challenge elections that might arise before the deadline.

That argument appeared to persuade U.S. District Judge Stephen Wilson, who presided over the 2002 settlement and ruled against most of the same civil rights plaintiffs in the current case. But it did not seem to carry the day in the 9th Circuit.

Thomas said part of last year's pact was postponement of the vote on Proposition 54 until the punch-card machines could be replaced.

Woods replied that "everybody knew" that setting a special election such as the recall could result in moving up voting on the initiative.

"Everybody knew that such a provision had never been used before statewide," replied Judge Harry Pregerson of Woodland Hills, the third member of the 9th Circuit panel. "Nobody thought about it."

American Civil Liberties Union lawyer Mark Rosenbaum, the plaintiffs' chief attorney in both the 2002 case and the current one, said Los Angeles has had more snow days than California has had recall elections.

Nevertheless, said Woods, the "integrity of the process" required the civil rights organizations to take the law as they found it.

"We have to take the law as it's found in the equal-protection clause as well," said Pregerson, referring to the 14th Amendment provision that was the basis of the Bush v. Gore decision to halt Florida's ballot recount because of county-by-county disparities.

In another Bush v. Gore reference, Thomas mentioned a finding made by former California Secretary of State Bill Jones, in decertifying the punch-card machines, that they were "unacceptable in California."

Woods said Jones only meant, "For California they're not good enough."

But Pregerson asked, "We have to accept the unacceptable?"

Arguing on behalf of recall proponent Ted Costa, attorney Charles Diamond said all types of voting machines cause errors.

"We can always do it better," a situation that won't change after punch cards become history, he said.

That argument appeared to carry some force, though how much was unclear.

In response to Rosenbaum's presentation, Judge Richard Paez of Pasadena said perfect voting equality was unattainable.

He also noted that decertification of California's punch-card machines won't become effective until next year. And he said Kevin Shelley, the current secretary of state, acted within his authority in accelerating the vote on Proposition 54 as well as Proposition 53, an initiative concerning infrastructure funding