The memorandum on White House stationary, dated June 4, 1969, marked "TOP SECRET SENSITIVE" at top and bottom, begins:

"Express your appreciation to Mr. Hoover and Mr. Sullivan for their outstanding support in recent weeks in uncovering security problems within the NSC staff. Inform Mr. Hoover that you have discussed these problems in detail with the President (and with Messrs. Hickman and Elhrlichman)."

The writer was then-colonel Alexander M. Haig Jr., at the time a member of the National Security Council staff. The recipient was Haig's boss, Henry A. Kissinger. The purpose of the paper was to prepare Kissinger for a 9:30 a.m. meeting that morning with FBI Director J. Edgar Hoover.

Ronald Reagan's selection of Haig to be his secretary of state is a controversial appointment in part because of the role Haig played in those early months of the first Nixon administration. As this little-noticed memorandum that now lies in the records of a complex civil suit demonstrates, Haig was deeply involved in the program of wiretaps of government officials and reporters.

According to the records of the FBI, Haig was the White House official who formally requested 12 of the 17 wiretaps the White House initiated in those months. When questioned about this later, Haig testified that he could not remember requesting all of those wiretaps. He also insisted that the only names he ever gave to the FBI were supplied to him by either President Nixon or national security affairs adviser Kissinger. Haig is likely to be asked again about this episode when he goes before the Senate Foreign Relations Committee next month.

The "outstanding support" from Hoover that Haig referred to in that June 1969 memorandum were the raw logs and summaries Haig and Kissinger had seen of FBI wiretaps that had been placed during the prior four weeks on five Kissinger staff members (and thus Haig's colleagues), plus Defense Secretary Melvin Laird's personal assistant and a British journalist who was a close friend of Kissinger.

By the time Kissinger was set to sit down with Hoover on June 4, the FBI had put together at least three detailed logs of conversations from the home telephone of Morton H. Halperin, one of the tapped NSC staffers. And Haig himself had visited FBI assistant director William Sullivan, at the latter's request, at least once to read those logs. Within a year he was to have made three other such visits to the FBI.

By June 4, two summaries of Halperin's conversations -- and some of his wife's -- had been sent by Hoover to Kissinger. Another report on the tap of NSC staff member Daniel Davidson had also been provided by the FBI director to Nixon as well as Kissinger.

What the June 4, "talking points" paper written by Haig shows, however, is that he was the NSC's operations officier for the controversial and highly secret program that was to become a major count in the House Judiciary Committee's impeachment case against nixon.

The specific "security problems" that Haig's paper said Hoover's wiretaps helped uncover have yet to be fully disclosed. The generally stated aim of the wiretap program was to stop what Nixon and his top staff, led by Kissinger, considered a series of "leaks" of security information to reporters.

At a meeting on April 29, 1969, Nixon, Hoover, then-attorney general John Mitchell and Kissinger discussed the need to take some strong action if leaks persisted. (Haig was not present at this meeting.) Wiretaps were mentioned as one option by Hoover, according to Kissinger and others, and the FBI Director was given authority by Nixon to do whatever he believed necessary to find the leaker, the next time one occurred.

Eventually, however, the wiretaps were more useful for the political intelligence they provided than for protecting any national security information, according to findings of the House Judiciary Committee compiled during its impeachment proceedings against Nixon.

The taps began on May 9, 1969, on Halperin's home phone in the wake of a Kissinger complaint to Hoover about a New York Times story. The article disclosed the United States had been secretly bombing in Cambodia. Kissinger has since maintained that Nixon urged him to complain to Hoover.

The next day, Haig -- in his new role as NSC operations officer for the tapping -- visited Sullivan with the first of the names of the 17 individuals that would be tapped under the program.

What Haig has repeatedly said, however, is -- as he told the Senate Foreign Relations Committeed in 1974 -- "I never would have submitted a name that I did not get from Dr. Kissinger, or from the president with Dr. Kissinger's knowledge . . . ."

Haig and Kissinger in their testimony in various forums have presented an ambiguous view of the wiretap program.

As Haig said at one hearing: "We thought it was necessary. At the same time, I felt it was an awful lot of garbage involved in it."

Haig, however, often refused to be defensive about the wiretaps, frequently using an old rumor, spread by Hoover, to justify the whole program. At one hearing he declared, "In one instance, one of those people was a very, very prime suspect for espionage activity . . . . It was a person who was alleged to me informally to have been an agent of a foreign government."

Haig was never asked at this session who that person was. But Hoover had early in the program spread the word that British newsman Henry Brandon, Washington correspondent for the Sunday Times of London, was a foreign spy, supposedly in the employ of either British or some communist country's intelligence service -- an allegation that was refuted by many top U.S. officials who had reviewed the journalist's FBI records.

Haig's reference, if indeed it was meant to apply to Brandon, was somewhat ironic. Brandon was a close friend of Kissinger's, and interveiwed him regularly. And although the Brandon tap was kept on longer than any other except for Halperin, Brandon was given an exclusive interview with Nixon shortly after it was removed.

There was another Haig-Kissinger view of the tapping, reflected in Haig's statement to the Senate committee that "Dr. Kissinger , at the outset of this program was very concerned that he and we were suspect because of the character of the staff that we had put together . . . ." In short, this was an investigation of the NSC staff being monitored by the only people Hoover and Nixon trusted.

That attitude -- that Kissinger and his aide were themselves suspect -- is apparent in Haig's June 4, 1969, memorandum to Kissinger, with its advice that Kissinger adopt an ingratiating approach to the FBI director.

For example, Haig's third point for Kissinger to make is, "Ask Mr. Hoover for his views on how we could proceed with Halperin, who has been involved in indiscretions and who obviously has a reputation for liberal views but who has yet to be firmly linked with a security breach."

Haig goes on to suggest that his boss hide his own feelings. "I think it best that you seek Mr. Hoover's advice in this instance while avoiding any specific comments pro or con and especially avoiding any opinions on this matter." It was the sort of careful bureaucratic formula that Haig himself has followed in his long career.

The final point on Haig's June 4 memo hinted at the strains the wiretapping program caused for Haig and Kissinger. "Ask Mr. Hoover if he has any additional information or guidance which he feels would be helpful in this very difficult situation," Haig wrote.

Haig added parenthetically, "I think in the case of Halperin and Brandon that they should be kept on for at least another two weeks so that a pattern of innocence can be firmly established." In fact, the taps remained on Halperin's and Brandon's telephones for another year and a half.

Haig has volunteered one memory on an aspect of the wiretaps that raises a question about his role in withholding information from the judge who tried Daniel J. Ellsberg, the man who made public the Pentagon papers.

On April 25, 1973, while he was Army vice chief of staff, Haig took the stand in the closing days of the Ellsberg trial as a surprise rebuttal witness for the government. The purpose was to undermine Halperin's testimony as an expert witness on Ellsberg's behalf.

When Haig testified, he was one of the handful of people who knew that Ellsberg had been overheard on the then-secret wiretaps. In fact, Haig knew from the summaries that Ellsberg had been heard on the tap of Halperin's phone. Because the government had previously given assurances that Ellsberg had not been picked up on any federal wiretaps, however, this matter did not come up when Haig testified at the trail.

Nine days later, Haig was named Nixon's chief of staff. That same day, May 4, 1973, newly appointed acting FBI Director William Ruckelshaus started an inquiry into the White House wiretapping program because, as he said at the time, "I was informed by FBI employes that those [wiretaps] had been performed and that the records relating to them were missing from the FBI files."

The story of the hiding of the wiretap records and their subsequent discovery has never been fully explored. Because Haig was a key participant, his confirmation hearings might provide an opportunity to clear up this loose end of Watergate.

The issue is whether the wiretap records were hidden in the White House to avoid having to produce them for the Ellsberg trial.

The story starts two years earlier, on July 2, 1971, when FBI Director Hoover was requested by Robert Mardain, then an assistant attorney general, to search for any wiretap records showing that conversations involving Ellsberg had been picked up. This was a routine procedure in conjunction with the opening of pretrial activities in Ellsberg's case. A week later, another search was requested for any signs that Halperin had been tapped by the FBI.

Within days, Sullivan told Mardian of the White House taps. On July 11 Mardian spoke directly to Nixon about what to do with the records, which contained material on Ellsberg and Halperin.

Nixon, according to Mardian, ordered him to collect the records and bring them to the White House.

This was done, Mardian later told the FBI, and Haig and Kissinger participated in determining that all the logs they knew about were there.

On July 12, Hoover sent Mardian official notice that there were no wiretap records on Ellsberg; three days later Hoover sent the same notice for Halperin. In neither message did Hoover refer to the taps whose records were then at the White House.

Thus, when the Ellsberg trial started, no information was provided on the taps that had covered both the defendant and his key defense witness.

In May 1973, two years after the government originally assured the judge in the Ellsberg case that there were no wiretaps that would affect the proceeding, Ruckleshaus had to inform the court that this was not true. Ruckleshaus also had to tell the judge that he could not locate records of the tap that did pick up an Ellsberg conversation.

Haig, by then Nixon's chief of staff, was one of the few men who knew where those records were -- in the White House. But he said nothing publicly at the time.

However, when Haig gave a deposition in October 1974, in a civil suit brought by Halperin against the government, he said: "One of the first things that was brought to my attention [when he became chief of staff] . . . was the fact that the Ellsberg trial was in a hung-up state because the judge out there had requested any electronic surveillance that may have taken place on Mr. Ellsberg."

Haig went on, "I told Mr. [Leonard] Garment [then White House counsel] . . . that I knew there had been some such a wiretap and we should send it out to the judge. We then got in touch with Mr. Ruckelshaus and with Justice."

Ruckleshaus' public statements at the time and the FBI record that has been made public since do not suggest that Haig played any role at all in locating the wiretap records. According to these records, it was Sullivan, who had then left the FBI, and Mardian, who had left the Justice Department, who pointed Ruckleshaus to the White House in his search for the wiretap records.

Haig, however, maintained in 1974 that "I instituted a search in the White House, and lo and behold, we found . . . them in Ehrlichman's files, in a cardboard box so big."

Garment does not remember Haig's version and Ruckelshaus has been unavailable for comment. Haig, however, could clear up -- perhaps with the help of some White House tapes of presidential conversations -- whether the wiretaps were hidden in 1971 to avoid their disclosure at the Ellsberg trial and why he did not step forward on May 9, 1973, and declare their existence.

On June 20, 1975, the Watergate special prosecutor summoned Haig to appear before a federal grand jury in Washington to testify about his role in the wiretaps. The contents of that testimony, which is sealed by the court, has never been revealed.