Updated

The Bush administration's warrantless wiretapping program has a built-in feature the Justice Department believes may shield it from ever being challenged as unconstitutional: secrecy.

The administration has acknowledged it intercepted some U.S. telephone conversations without warrants as it hunted for terrorists.

Whose calls? The government isn't saying. And since only those who were spied on have grounds to sue, it's almost impossible to mount a successful legal challenge.

A federal appeals court in Ohio dismissed one such challenge last month because the American Civil Liberties Union and other groups could not prove the government had listened to their conversations. The court did not rule on whether the program was constitutional.

Unless the government decides to release information about its wiretaps — as part of a criminal case, for example — the Justice Department said Monday the constitutional question may never be answered.

A senior Justice Department official made the comments at a briefing before a hearing Wednesday in San Francisco, where lawyers are trying to challenge the program's legality. The official, who insisted on anonymity because of the pending litigation, said such challenges must first clear a difficult hurdle.

"They would have to somehow get, through discovery or admission from government, that they had in fact been surveilled," the official said.

Attorneys for an Islamic charity say they can prove just that. Because of a government mix-up, the Al-Haramain Islamic Foundation received what charity attorneys said was a National Security Administration log of calls intercepted between the charity and its lawyers. Armed with that information, the charity is challenging the program in a San Francisco court.

Justice refuses to say whether the charity's calls were intercepted, but it wants the case thrown out because defending it would require the government to disclose state secrets.

Asked whether the Justice Department saw any way someone could challenge the surveillance program, the official replied, "In the current context, 'No."'

The U.S. Supreme Court has held that people can't sue merely to right a wrong. They must have standing, meaning they must be able to prove they were harmed by the government's behavior. Even if it might mean nobody will ever have standing to sue, the Supreme Court has said that proof is required.

"Without that, I think there is that Catch-22," said Charles Fried, who served as solicitor general under President Reagan.

Before adjourning for the summer, Congress hurriedly approved a bill authorizing intelligence officials to intercept conversations between foreign suspects and U.S. citizens without seeking a warrant.

ACLU's legal director, Steven R. Shapiro, said he hopes lawmakers revisit that bill when they return to work. And he said he remains confident that the program's secrecy will not shield it from review forever.

"Sooner or later, in one of these cases, we're going to have the court review this wiretap program," Shapiro said. "I have no doubt about it."

Meeting in San Francisco on Monday, the American Bar Association overwhelmingly passed a resolution urging judges to avoid dismissing cases solely because the government says the cases involve state secrets. That's the argument the Justice Department plans to make in court Wednesday.

Most courts side with the government when it says a case can't go forward without risking the disclosure of secret information. But the lawyers' organization, which has repeatedly opposed Bush administration legal actions involving terrorism, said judges should have greater discretion to assess those claims.

"The government at any time can overreach and over-assert," said Lawrence Fox, a lawyer from Philadelphia who has worked on state secrets issues. "I urge you to have confidence in our judges to protect us from overreaching by the government."

Judges would be allowed to evaluate the information the government says is secret as well as whether unclassified material may be substituted in order to allow the lawsuit to proceed, under the resolution adopted by the ABA.

The lawyers group also urged Congress to overturn the order President Bush signed last month allowing harsh CIA interrogations of suspected terrorists. The ABA, with little dissent, said the order violates international treaties governing detainee treatment and makes it more likely that other countries will subject captured U.S. soldiers to similarly harsh treatment.

The administration said the order explicitly bars the use of torture and complies with international treaties.