Walsh and Staff Strive to Avoid News of Probe : To Obtain Indictments, He Must Prove They Aren’t Based on Immunized Witness’ Testimony

The aide to independent counsel Lawrence E. Walsh seemed genuinely alarmed when she spotted the newspaper under the visitor’s arm. “There are no North stories on that page one, are there?” she asked.

Only after it had been determined that there was none did Walsh enter the room for a scheduled interview with The Times on Thursday.

The precaution is one of a series that Walsh, his 26 associate counsel and 35 FBI agents assigned to the Iran- contra investigation are taking to avoid being exposed to the words of witnesses testifying under grants of limited immunity from prosecution.

A Heavy Burden

If an independent counsel is to obtain grand jury indictments of anyone who testified under immunity, he must prove that none of his evidence was derived directly or indirectly from the individual’s testimony, which prosecutors consider a heavy burden. Walsh noted that not one person who testified with immunity in the Watergate scandal was convicted at trial, though some did plead guilty.

“We’ve done well so far,” Walsh said. But he added that the coming testimony on Capitol Hill by Lt. Col. Oliver L. North and his former boss, Rear Adm. John M. Poindexter, “will be the most difficult test.”

It is considered certain that North’s attorney, Brendan V. Sullivan Jr., will challenge any indictment of his client on grounds that the evidence against his client came from his immunized testimony. Sullivan has captured Washington’s attention by employing sweeping and imaginative legal maneuvers to thwart his client’s prosecution.

Walsh’s concern about satisfying the heavy burden has spread to the House and Senate committees investigating the sale of U.S. arms to Iran and the diversion of profits to the Nicaraguan rebels.

Court Proceedings Feared

When North finally appeared this week for closed-session questioning by the panels, only six of the 26 members showed up. A chief reason, committee aides said, was the fear that if any information did leak from the session, the members could become embroiled in lengthy court proceedings as North’s attorneys attempt to prove that the prosecution had been tainted by this information.

In Walsh’s office, one FBI agent, one associate counsel and his public affairs aide, Gail Alexander, have been allowed to be exposed to the televised hearings and published accounts of the testimony in their liaison and other assignments.

“The rest of us are not reading any stories about immunized testimony,” Walsh said.

Similar Precautions

Although Walsh would not discuss it, the federal grand jury here taking testimony in the Iran-contra probe and related investigations is operating under similar precautions, its members instructed not to watch the hearings or read news accounts of the testimony.

“I don’t think there has been any investigative group confronted with the volume of public exposure we’ve had,” Walsh said. “We’ve all worked out something” to avoid such taint, he said.

Walsh said he does not watch the evening news broadcasts on television until he completes his daily call to his wife in Oklahoma City, who “tells me whether I can see the news that night.”

Next week, as North answers questions publicly for the first time, “it will be like we’re on a camping trip where you don’t have newspapers,” the independent counsel said.

Need for Completeness

Walsh refused to say why he did not push for any action against North and others before they appear under the limited immunity grants. But a source familiar with the investigation said the advantage of bringing charges swiftly has to be balanced against the need for completeness.

In investigations as complex as the Iran-contra probe, it is likely that a superseding indictment may be brought as new information is gathered, a development that would raise again the question of taint from immunized testimony.

Each week, Walsh’s office delivers to chief U.S. District Judge Aubrey E. Robinson Jr. sealed evidence collected on targets of the probe.

Although Walsh would not comment on the issue, many expect that his office will seek no indictments until the congressional hearings complete their public sessions.