The government does not have to reveal whether it is monitoring the conversations of an attorney accused of helping a jailed Egyptian cleric direct terrorism, a judge ruled Thursday.

In his decision, U.S. District Judge John Koeltl denied a motion by the attorney, Lynne Stewart, that would have forced prosecutors to disclose whether they were listening to her conversations with her clients. Stewart's co-defendant, U.S. postal worker Ahmed Abdel Sattar, had joined in the request.

The judge said the defendants had not explained how the government's "legitimate interest in engaging in covert investigations of ongoing criminal activity or for foreign intelligence purposes could be maintained if the government were required to disclose any such investigations in advance."

The government is allowed to obtain court orders to eavesdrop on discussions between attorneys and clients using powers authorized by Attorney General John Ashcroft after the Sept. 11 terrorist attacks.

"His ruling makes clear that if they [the government] don't follow the law, they'll be held accountable for it," said Stewart's attorney, Michael Tigar. "They just won't be held accountable for it right now."

Stewart and Sattar are charged with helping relay messages from Sheik Omar Abdel-Rahman to the Islamic Group, an Egyptian-based terrorist organization. They have pleaded innocent.

Stewart, free on bail, represented Abdel-Rahman, a blind cleric serving a life sentence for conspiring to blow up New York City landmarks in 1993.

Tigar had argued that Stewart needed to prepare a joint defense with Sattar -- who had acted as interpreter for Abdel-Rahman -- but feared that any "shared information will tumble into the government's hidden hands."

Sattar's lawyer, Kenneth Paul, had argued the government's refusal to say whether it was monitoring conversations had a "chilling effect" on their talks.

The government had already assured the judge that Sattar was not under surveillance, Paul said Thursday.