WASHINGTON — Congress' investigations of the Iran- contra affair have turned up nothing so far that would prevent Ronald Reagan from finishing his presidency on "a relatively high note," the vice chairman of the Senate investigative panel said Monday after reviewing voluminous evidence compiled in the inquiries.
However, Sen. Warren B. Rudman (R-N.H.), who says that the evidence contains "the greatest paper trail I've seen in my life," cautioned that further damaging disclosures cannot be ruled out.
"The one unknown factor is what North and Poindexter will say," Rudman said, referring to the scandal's central figures, Lt. Col. Oliver L. North and former National Security Adviser John M. Poindexter, who so far have refused to testify. "It could open up other avenues."
Rudman, speaking in a luncheon session with reporters, said Poindexter will be the "most important" witness in the upcoming congressional hearings because he was at the heart of the Iran arms sale policy, met frequently with the President and can tell members whether Reagan was ever informed of the diversion of Iranian arms sales profits to the Nicaraguan rebels.
Rudman said he does not "expect Poindexter or North to be anything but truthful when they testify."
The President has denied any knowledge of the diversion of funds, the most inflammatory aspect of the affair. And none of the evidence developed so far has indicated any culpability on Reagan's part that might jeopardize his presidency, said Rudman, a one-time prosecutor and former New Hampshire attorney general.
Agreement on Immunity
Meanwhile, attorneys for the House and Senate select investigating committees reached a tentative agreement Monday that calls for granting limited immunity from prosecution to Poindexter to compel his testimony. Sources said the committees have no immediate plans to grant immunity to North but that he is expected to be granted immunity later.
Both Poindexter and North, who served as his aide until both lost their White House posts after the diversion of funds to the contras was disclosed, have invoked the Fifth Amendment right against self-incrimination in refusing to provide their accounts of the affair.
Lawrence E. Walsh, the independent counsel who is conducting a criminal investigation into the affair, had asked the committees to delay voting immunity for any witnesses for at least 90 days to avoid interfering with his inquiry.
Under the committees' plan, private testimony from Poindexter would be taken within 60 days, but it would be at least 90 days before he testifies at a public hearing.
The pact between the committees will be presented today to Walsh as a proposed compromise to his request for a 90-day delay. Walsh is expected to agree to the plan even though it does not provide for the full delay he sought. If Walsh does agree, the committees will approve the plan formally at a meeting scheduled for Wednesday.
The limited immunity granted would prevent prosecution based on the witnesses' own testimony. It would not rule out prosecution through evidence developed from other sources.
Rudman suggested that the congressional committees will not begin their hearings until about mid-May and said that by that time Walsh will have "all the necessary information" he needs for any prosecutions resulting from his investigation.
There has been "complete cooperation" between the 11-member Senate investigating committee and the 18-member House committee, Rudman said, and a majority of the public hearings being planned will be conducted jointly by the committees.
The senator, echoing other comments on Capitol Hill that public disclosure should take precedence over prosecution in the affair, said the congressional investigations are "far more important" than the independent counsel's work. And Walsh, he said, has agreed that Congress' role is primary.
Discussing evidence already turned up by the Senate committee, Rudman said Administration officials involved in the affair left an enormous trail of evidence except in the case of meetings involving the President.
"For some reason," he said, there were not many notes about Reagan's meetings, but otherwise those involved, sometimes apparently not realizing how much they were leaving on the record, wrote details of "what was being done and who was doing it."
Focus on Arms Deal
The congressional hearings, Rudman said, probably will focus more on the policy of selling arms to Iran than on the diversion of funds to the contras and will concentrate on three major areas:
--The origin of the policies and the way in which they developed.
--The diversion of funds and how that was handled.
--Private action taken on behalf of the contras that was aided and abetted by U.S. government representatives.
The criminal investigations, he said, are focusing on obstruction of justice, destruction of records, possible perjury and violation of a law that banned U.S. aid for the contras--direct or indirect--until Congress approved such funding.
Based on his own experience as a prosecutor, Rudman said any prosecution that might result from the investigations "will not be easy."