There is no evidence of any conspiracy to sabotage the politically sensitive investigation. But the inquiry, begun at the request of Congress by the Government Accounting Office (GAO), was never completed, and no report was ever released. Such a report might have shed light on George Bush's knowledge of the United States' ties with Noriega just at the time that Bush was campaigning for the presidency.

Bush was director of the Central Intelligence Agency while Noriega was a paid CIA informant. Because Noriega was also reportedly involved in drug trafficking at that time, the question of whether Bush was aware of the Panamanian dictator's illicit activities became an issue. At one point in the campaign, Bush trailed Michael Dukakis in the polls by as much as 20 percentage points, a deficit then attributed in part to Bush's Noriega problems. Dukakis attempted to keep the issue alive during the campaign, but it eventually faded. Bush has yet to comment publicly on the matter, citing national-security concerns.

The collapse of the GAO inquiry is detailed in a chronology kept by one of the investigators. According to that record, shortly after the probe was initiated, between May 11 and May 16, 1988, the GAO "sent routine notification letters to the Departments of State, Justice, and Defense, and the National Security Council, advising them of our review and identifying the subject and scope of our work." The CIA was notified soon afterward.

But GAO officials found that officials of the State Department, Justice Department, Customs Service and Drug Enforcement Agency among others refused to provide access to needed documents. Officials at several agencies told investigators that they could not assist the investigation until officials at the NSC gave the go-ahead. On June 8 and June 9, 1988, the chronology states, the GAO investigators were "advised" by officials at State and Justice that the "NSC instructed them not to deal with us until [the] NSC had developed operational guidelines on what to to do and what not to do on this assignment."

GAO investigators were surprised by the reaction. Only days earlier, on June 6, they had met with Dan Levin, the NSC's deputy legal adviser. At that meeting, says the chronology: "Mr. Levin stated we are free to deal with each agency directly and that [the] NSC would not be a bottleneck."

A spokesman for the NSC said in an interview that he could not comment because the matter involves an administration no longer in office. But the spokesman said information contained in NSC files reflected that the Reagan administration did not cooperate with the GAO probe because the GAO had gone "beyond GAO's statutory authority" and had asked for "extremely sensitive intelligence and law-enforcement information." The spokesman added later: "There was no attempt to withhold information to which GAO was legitimately entitled."

Nancy Kingsbury, a senior official in GAO's National Security and International Affairs Division, said that the NSC's coordinating activities were unusual. "The NSC would not ordinarily have played that kind of role," Kingsbury said. "That was certainly unusual. The people in my division could not remember any other instance of agencies being directed not to cooperate with us by the NSC."

On June 13, the CIA also informed the GAO that it would not cooperate with the probe. In a letter to the GAO, John L. Helgerson, the CIA's director of congressional affairs, stated: "All Agency activities in Central America, as well as information we receive concerning other U.S. Government activities in the region, are subject to close and continuing scrutiny by the House and Senate Intelligence Committees." Saying that he was responding on behalf of CIA Director William Webster, Helgerson then stated that the CIA thus could not cooperate.

On June 22, GAO investigators "held a second meeting with the NSC and White House staff personnel." Among those attending was Nicholas Rostow, a special assistant to the president and legal adviser for the NSC. The GAO once again requested NSC cooperation. The chronology noted: "They [the White House] promised a prompt response." But the NSC failed to respond to the GAO despite at least 15 requests to NSC and other officials over a three-month period, according to the investigative chronology.

On Aug. 8, the NSC told the GAO it was still considering its request. On July 22, however, NSC Executive Secretary Paul Stevens had already sent the directive to the Departments of State, Defense, Treasury, and Justice, as well as the CIA, instructing them not to assist the GAO.

Citing what it said were "legal issues requiring in-depth analysis," the directive instructed its recipients that "[T]here should be no meetings with GAO, and no documents or other information should be provided to GAO" until NSC completed a legal analysis. The result was that no executive agencies cooperated with the probe, and the GAO was unable to complete its investigation.

Other evidence suggests that the stymying of the GAO probe may have been part of a broader effort by Reagan officials to keep the potentially embarrassing Panama story out of the news. On Sept. 29, 1988, for example, The New York Times listed several instances of harassment of U.S. military and diplomatic personnel in Panama following the indictment of Noriega in this country on drug trafficking charges. Mid-level U.S. diplomatic and Pentagon officials reportedly were complaining that the administration was not protecting its personnel.

Citing "several administration officials" as sources, The Times reported: "After the collapse of the American-led negotiation to remove General Noreiga from power last summer, the White House made clear to other agencies that negative publicity about the Panama policy should be kept to a minimum, especially as the presidential campaign intensified . . . ."

Meanwhile, Rep. Sam Gejdenson (D-Conn.) was investigating a more than $ 50 million shortfall in a U.S. Treasury Department escrow account set up for U.S. corporations doing business in Panama. On April 8, 1988, then-president Ronald Reagan signed an executive order directing that such corporations no longer pay taxes, tariffs, excise fees, and other monies to the Noriega regime. The directive required the companies instead to place the funds in an escrow account maintained by the Treasury Department at a Federal Reserve Board bank. Once Noriega resigned or was overthrown, the funds were to be turned over to the new Panamanian government.

Gejdenson revealed at a congressional hearing last Oct. 6 that the escrow account was at that time an astonishing $ 65 million short of anticipated collections, and that less than $ 4 million was then in the account. Gejdenson says that he and his staff attempted to investigate, but were resisted by senior Treasury Department officials. Claiming that there was "no question that stonewalling by the Treasury Department and [then-secretary of the treasury] Baker took place," Gejdenson charged that Baker "wanted to keep everything about Panama off the front page" until after the election was over.

A spokesman for the secretary of state would not comment on Gejdenson's remarks. In the meantime, Gejdenson has asked the GAO to investigate the shortfall in the escrow account. Murray Waas is a Washington-based journalist who has written extensively on national-security issues.