Even before Watergate brought down his presidency, Richard Nixon was the prime mover in another illegal action that could have been grounds for impeachment.

It is now clear, after extensive research, that Nixon initiated the campaign to sabotage the My Lai massacre trials so no American soldier involved in the killings would be convicted of war crimes.

Working with the president in this campaign were his chief of staff, H.R. “Bob” Haldeman; one of his top propagandists, congressional liaison Franklyn “Lyn” Nofziger; and two of the leaders of the House Armed Services Committee, congressmen L. Mendel Rivers (D-SC) and F. Edward Hebert (D- La.).

The smoking gun is a series of notes by Haldeman from a meeting with the president, an overlooked part of the Nixon papers. The notes are stored in the Nixon Presidential Library in Yorba Linda, Calif.

The Haldeman meeting, on Dec. 1, 1969 was one of several in which Nixon struggled to figure out how to get control of the worsening public relations nightmare that the massacre brought down on the US government. The wartime atrocity had occurred not on Nixon’s watch, but during the administration of his predecessor, President Lyndon Johnson. Nevertheless, it was now Nixon’s problem.

He would have to deal with the fallout from one of the darkest chapters in US military history.

‘How come you ain’t killed them yet?’

The massacre — in which 504 unarmed Vietnamese civilians were slaughtered by out-of-control US soldiers on March 16, 1968 — had been covered up successfully for more than a year by officers in the chain of command in Vietnam at the time.

A letter from former soldier Ron Ridenhour — sent to the president, the chairman of the Joint Chiefs of Staff, the secretary of the Army and about a dozen congressmen and senators — finally exposed the massacre.

By November 1969, newspapers across the country were on to the story. The Cleveland Plain Dealer published photographs of women, old men, children, even toddlers lying dead on a dirt road at My Lai — irrefutable evidence. That same month came a stunning television interview by Mike Wallace of CBS News in which ex-G.I. Paul Meadlo confessed publicly to shooting Vietnamese of all ages.

“There was about 40-45 people that we gathered in the center of the village,” Meadlo said. “Men, women, children . . . babies. And Lieutenant [William] Calley came over and said, ‘You know what to do with them, don’t you?’ And I said yes. I took it for granted that he just wanted us to watch them. And he left, and he came back 10 or 15 minutes later, and he said, ‘How come you ain’t killed them yet?’ And I told him that I didn’t think you wanted us to kill them . . . and he said, ‘No. I want them dead.’”

New revelations were being published or broadcast at a dizzying pace. The American people were disillusioned and disgusted. Some were simply in denial.

Nixon and his advisors had been over this subject many times before in the previous six to eight months. Now it was clear that the need for damage control was even greater than they’d originally thought.

Not one to cower, Nixon’s style was to attack major problems. He was fond of saying one does not coast to victory but must fight to win.

Accordingly, on Dec. 1, 1969, he sat down with Haldeman — the chief enforcer of the president’s will — and began describing how the administration would approach the crisis.

First, Nixon ordered that a group of advisors, some of his best thinkers, be organized into a “My Lai Task Force.” He wanted input from them on political, military and public relations fronts.

The group would include Pat Buchanan, special assistant to the president for media analysis and speech writing; Henry Kissinger, national security advisor; Herb Klein, director of communications for the Executive Branch; and Nofziger, whose job was to get members of Congress to support Nixon’s policies and plans.

The president then authorized Haldeman to minimize the damage to the reputation of the Army.

Haldeman’s note says Nixon approved the use of “dirty tricks . . . (but) not too high a level.”

“Discredit one witness,” Nixon said, according to Haldeman’s notes.

Nixon was referring to Hugh Thompson, the man who was emerging as the star witness for the prosecution of the crimes at My Lai — the Army helicopter pilot who had confronted and countermanded superior officers while interfering in the ground operation at My Lai.

“[We] may have to use a senator or two,” Nixon said as Haldeman took notes.

Haldeman had his marching orders.

The shadow campaign

Nixon routinely used congressmen and senators to do his bidding, to make charges for which he didn’t want to take responsibility, according to Nixon tapes expert Ken Hughes of the University of Virginia’s Miller Center’s Presidential Recordings Program. Nixon sometimes had his aides write speeches or talking points for the lawmakers, who would deliver them as if they were their own, Hughes explains.

The day after the meeting with Nixon, the record shows Haldeman met with Nofziger.

Nofziger would write in his autobiography, published in 1992, that his job involved attacking and discrediting people and legislation that ran counter to the president’s will.

“I was to persuade members of the House and Senate to praise the president when he did well . . . and to support him vocally in the things he was attempting to do, and to attack those who attacked him,” Nofziger wrote.

Seeking help from the most pro-military members of the House of Representatives fell within Nofziger’s job description. Following his meeting with Haldeman, Nofziger met with Congressman Rivers, a conservative Democrat from South Carolina. The chairman of the House Armed Services Committee, Rivers was a dependable ally of Nixon’s in all things military.

Rivers was in the business of supporting the best interests of the US military and promoting their image as honorable, effective fighting men.

Though Rivers wasn’t sure how he could help the president achieve his goals, he was sure he would come up with something.

For openers, he was adamantly opposed to the prosecution of any US soldier for what happened at My Lai. Rivers wanted the president to rest assured that he could count on him in this most difficult of times.

Sabotage

Just a few days after meeting with Nofziger, Rivers set up a special investigating subcommittee of the House Armed Services Committee. Rivers was chairman of the HASC and would also serve as interim chairman of the new investigating subcommittee.

The announced purpose of the subcommittee was to conduct an independent congressional inquiry into the truth of the allegations that US troops had committed atrocities against civilians at My Lai.

The actual purpose of the subcommittee was to serve as a mechanism to sabotage the My Lai massacre trials — in keeping with the president’s will to prevent the conviction of any soldier who may have committed a war crime at My Lai.

Meanwhile, the Army was conducting its own investigation. It did not appreciate what it saw as inappropriate congressional interference.

The HASC investigating subcommittee proceeded to use its subpoena power to compel the appearance and testimony of virtually all material witnesses to the crimes at My Lai. This meant all the key prosecution witnesses, including Hugh Thompson.

For a week in December 1969 and later for 2¹/₂ months, beginning in mid-April 1970, the subcommittee took testimony, in secret sessions, from soldiers with firsthand knowledge of the massacre and its coverup.

But the subcommittee sealed the testimony and refused to share it with the defendants’ lawyers. This maneuver was a violation of what is called the Jencks Act — which says that the government must release evidence in its possession, including testimony of material witnesses upon the request by the defendants’ attorneys.

The subcommittee’s chairman — first Congressman Rivers and later Congressman Hebert — refused to release the testimony.

One of the criminal cases collapsed as a direct result, as Thompson and other prosecution witnesses were barred by the judge from testifying in that case, and lawyers couldn’t use the Congressional testimony.

The judges in five other cases refused to apply the Jencks Act, arguing that they could obtain the same testimony from the key witnesses in their own courtrooms.

Secretary of the Army Stanley Resor was keenly aware of what Rivers and Hebert were up to, and he protested angrily, saying their shenanigans were undermining the military justice system.

It was clear to Resor they were attempting to sabotage the upcoming trials. He wrote Hebert three letters urging him to postpone his hearings until after the Army’s courts-martial were complete.

Hebert did not comply.

Similar letters were sent to Hebert and/or Rivers by other congressmen, including Abner Mikva and Ed Koch, and co-signed by more than a dozen other congressmen.

One prosecutor, Col. William Eckhardt, was unequivocal in condemning Rivers’ and Hebert’s underhanded tactics. Eckhardt, now a professor of law at the University of Missouri at Kansas City, saw the scheme for it was.

“Hebert and Rivers decided that these trials were detrimental to the interests of the United States of America and they tried . . . to sabotage them,” Eckhardt charged.

‘Killing didn’t haunt me’

Moreover, Eckhardt added, besides trying to get Lt. Calley and the others off the hook, they tried to turn the tables on Thompson and set him up to be court-martialed for threatening the lives of fellow soldiers in his attempt to stop the killing of unarmed civilians.

“Another key to sabotaging the prosecution was to get Hugh Thompson,” Eckhardt observed, explaining that if Thompson were to be successfully discredited and intimidated into silence, then one to the pillars of the prosecution’s cases would collapse.

The subcommittee’s focused effort to discredit Thompson and to silence him was made clear in the pages of the transcript of the subcommittee’s hearing. (These records were sealed until 1976, after the trials and appeals process had run their course.)

Hebert and others badgered Thompson, trying to get him to confess under oath that he ordered his gunner to train his weapon on US soldiers at My Lai in his effort to stop the killing of civilians.

Thompson kept testifying against the butchers of My Lai in hopes of securing justice for the civilians killed that day. Thompson had become something of a professional witness.

But in the end, only one man was found guilty: Lt. William Calley was convicted of the premeditated murder of 22 Vietnamese civilians and sentenced to life in prison. More than two dozen men had been recommended for court-martial for war crimes and related misdeeds. Only five were tried. Four were acquitted.

Calley’s conviction brought on a convulsion of anger and protest among many US citizens and a flood of emotionally charged letters to the president and other top-ranking government officials. Nixon got 260,000 letters and 75,000 telegrams, most opposing the verdict.

Under pressure, Nixon interceded, releasing Calley from the stockade after three days and allowed him to live in his bachelor’s quarters at Fort Benning, Ga., under house arrest pending appeal of his conviction.

“We weren’t in My Lai to kill human beings, really,” he later said. “I was there to destroy an intangible idea. To destroy communism. Killing those men in My Lai didn’t haunt me.”

Calley was eventually placed on parole in 1974 after serving one-third of a twice-reduced sentence.

Trent Angers is the author of the newly revised “The Forgotten Hero of My Lai: The Hugh Thompson Story.” He is a veteran journalist, magazine editor and publisher and author of six books. He resides in Lafayette, La.