CIA agent who was sent to prison for four months in 1975 for his part in the Watergate burglary

It is somehow fitting that the death of James McCord – the CIA agent and Watergate burglar whose arrest then sensational trial in 1973 set in motion the scandal that eventually forced the resignation of the US president Richard Nixon – should have evaded public notice for almost two years.

McCord’s death in 2017, aged 93, was first reported in Shane O’Sullivan’s 2018 book Dirty Tricks, about the Nixon scandals, but it was not until it was mentioned on the website Kennedys and King last month that it was picked up by major media. In death, as in life, McCord remained in the shadows.

His role in the president’s downfall ostensibly began in 1971, when he left the CIA to work for the Nixon administration on the committee for the re-election of the president (popularly known as Creep), first with Jack Caulfield on Operation Sandwedge, gathering dirt on Nixon’s “enemies”, then with “the plumbers unit”, so-called due to its brief to plug information leaks.

On the night of 17 June 1972, McCord led his plumbers’ team of Frank Sturgis and three Cuban exiles into the Democratic National Committee offices in the Watergate building, to check on malfunctioning bugs they had planted there previously.

But a security guard, Frank Wills, noticed a taped-over door latch and called the police, who arrested the five burglars. The head of the plumbers unit, G Gordon Liddy, and another ex-CIA man, E Howard Hunt, who were overseeing the break-in from a room at the adjacent Watergate hotel, fled, but were later arrested.

Asked about his employment during arraignment, McCord whispered “CIA” to the judge, and the ears of the Washington Post reporter Bob Woodward perked up. A search of the hotel room abandoned by Hunt and Liddy revealed notebooks with White House contact numbers. The ensuing investigations into crime and cover-up moved to Congress, and, faced with impeachment, Nixon eventually quit, in August 1974.

During the trial, the White House had tried to fend off reports suggesting ties between the president’s men and what they called a “third-rate burglary” but in January 1973 McCord, who declined to say anything about his own career before Watergate, pleaded guilty along with the other four, and was sentenced to a prison term of one to five years. A month earlier, McCord had written to Caulfield warning the White House not to fire the CIA director Richard Helms, or “every tree in the forest will fall. It will be a scorched desert.”

However, having refused to aid Nixon’s cover-up, Helms was fired in February 1973. Soon after, Caulfield conveyed what McCord characterised as a mixture of bribery, threats, and promises of clemency to McCord, but it did no good.

In March, McCord wrote to the judge, John Sirica, detailing those offers and multiple perjuries by those giving the orders. He also stated flatly: “The Watergate operation was not a CIA operation. The Cubans may have been misled by others into believing that it was a CIA operation. I know for a fact that it was not.” As Sirica described it, the “trickle of information soon became a flood”, and the almost inevitable end of the Nixon presidency followed.

For co-operating, McCord had his sentence was cut to four months. Entering federal prison in Allenwood, Pennsylvania, in 1975, he said: “In the long run it has been extremely beneficial to the country to become aware of what occurred.”

But the question of exactly what occurred has been contentious ever since. Many researchers point to the awkward taping over of the latches, as many as six of them, the dawdling of the team in the DNC offices and the leaving of evidence in the Watergate hotel, as being uncharacteristic of McCord’s experience with tradecraft. This suggests a set-up, to get the White House operatives caught, and debate still persists about what material the DNC bugs were intended to discover.

Others point out that without McCord’s testimony, the whole investigation might well have been stone-walled and, rather than being frightened by White House threats, McCord may have spoken out of loyalty to the CIA to keep the investigation focused narrowly on Nixon. As Jim Hougan noted in his study of Watergate, Hidden Agenda, instead of the usual photo of Nixon on the wall, McCord’s Creep office featured one of Helms, inscribed, “To Jim, with deep appreciation”, with the “deep” underscored, as if with a nod and a wink.

Answers to some Watergate conundrums may lie in McCord’s CIA career. Born in Waurika, Oklahoma, he was the son of Marjorie (nee Welch) and James McCord Sr, a teacher. After high school he worked briefly at the FBI, then enlisted in 1943 in the Army Air Corps as a lieutenant. After the war he settled in Texas, where his parents lived, receiving his bachelor’s degree from the University of Texas. After a brief return to the FBI, he joined the still-young Central Intelligence Agency in 1951.

It is believed that as an operative McCord played a role in the Bay of Pigs invasion of Cuba in 1961, and developed ties then with Sturgis. McCord later testified that he and Hunt had never met before Watergate, but that was easily disproved; their association went back even before the Bay of Pigs, in which Hunt was a major player. This becomes particularly crucial in light of White House tapes revealing Nixon briefing his aide HR Haldeman on what to tell Helms in an effort to cut off Watergate investigations.

Nixon warns they will “make the CIA look bad … make Hunt look bad, and it’s likely to blow the whole Bay of Pigs thing”. While McCord’s Watergate team were veterans of the Bay of Pigs, Nixon’s reference appears to suggest other Cuba-related affairs, from CIA assassination plots against Fidel Castro, to the alleged involvement of some CIA people with Cuban exiles and the mafia in the killing of John F Kennedy in 1963.

Although McCord’s official title at the CIA was director of security, he was part of the “security research staff”, a unit specialising in covert and illegal operations, reporting directly to Helms. There he worked with David Atlee Phillips, often tagged as a JFK plotter, on the infiltration of the Fair Play for Cuba Committee; Lee Harvey Oswald, the alleged lone assassin of JFK, created his own one-man branch of FPCC in New Orleans, drawing attention to himself as a Castro supporter, which some say was a CIA-style “legend” identity. And O’Sullivan, in Dirty Tricks, quotes a source saying that Alfred Baldwin, a former FBI man brought into Creep by McCord, told him McCord was actually in Dallas the day Kennedy was killed, an allegation also levelled against both Hunt and Phillips.

After his release from prison, McCord founded his own security firm, McCord Associates, later called Security International. He taught security at a junior college outside Washington, and later founded a solar energy company in Colorado. In 1974, he published a memoir, A Piece of Tape, with the ambiguous subtitle The Watergate Story: Fact and Fiction. He had told Judge Sirica “I have no regrets in telling the truth,” but exactly what truth he told may never be clear.

His wife, Sarah Ruth (nee Berry) died in 2014. McCord is survived by his son, Michael, and daughters, Carol Anne and Nancy.

• James Walter McCord, intelligence operative and security expert, born 26 January 1924; died 15 June 2017