THE American wife of Erskine Childers is likely to have spied on Sinn Fein for the British government, according to a book to be published this week.

Michael Foy, a historian, says he has discovered papers suggesting British intelligence had a spy “at the very top of Sinn Fein” during the war of independence. During 1920 and 1921 its agent reported regularly on Eamon De Valera, Michael Collins and Arthur Griffith.

The spy, who was privy to sensitive information, was not identified in the papers, but Foy believes it is Molly Childers, whose son was president in the 1970s.

He bases the controversial claim in part on an analysis of the agent’s reports, which included American-sounding turns of phrase.

“That Molly Childers had the qualities to carry off such a dangerous role is not in doubt,” Foy writes in Michael Collins’s Intelligence War. “Throughout her life this remarkable woman displayed intelligence, courage, decisiveness and single-minded determination.”

The spy knew the terrible gamble she was taking. “I am risking my sanguinary neck every day, and all day,” she complained to her spymaster. “I wouldn’t get 10 minutes’ grace if they had the slightest suspicion.” Several British spies were executed by Collins’s men during the Anglo-Irish war.

The spy was close to a Sinn Fein leader she called Bob. Foy says this was either Erskine Childers himself, whose first name was Robert, or Robert Barton, a family friend.

Other clues are that she accumulated intelligence at informal gatherings where Sinn Fein leaders spoke unguardedly, while she had also participated in the British war effort between 1914 and 1918 and had fond memories of Britain.

“Only one prominent female Sinn Feiner fitted this profile,” says Foy, “and that was Erskine Childers’s wife, Molly.”

The daughter of a Boston doctor, Molly Osgood met Childers when his British army unit toured America. She had been crippled in a childhood skating accident and remained disabled throughout her life. They settled in London, and Childers was converted to the cause of Irish Home Rule.

Molly’s father had given her a 49ft ketch, the Asgard, which the couple used in 1914 to land arms at Howth for the Irish Volunteers. Childers served in the Royal Navy during the war, but in 1918 became a Sinn Fein politician. Foy says that Molly, who was awarded a CBE in recognition of her wartime work, was “distressed” by her husband’s decision to move to Ireland, and his Sinn Fein role put “considerable strain on their marriage”.

She agreed to move to Ireland with him in 1919, but Foy speculates that prior to that she volunteered “for British intelligence”.

The agent tells her handler that she took on the spying job “not for cash but to feel that I was really doing something to help”, adding: “I fell very strongly on this subject and I must let off steam or ‘bust’.”

Molly Childers certainly had access to senior Sinn Fein politicians, who regularly visited their home on Bushy Park Road in Terenure.

“As the hostess she provided hospitality and attentiveness while Sinn Fein leaders relaxed, socialised, gossiped and spoke more candidly than perhaps was wise,” said Foy.

While it is known from other sources that the British had high-level Irish spies at that time, other historians are likely to be sceptical that such an iconic figure was a British agent. “I would be willing to be convinced based on the evidence,” said Peter Hart, author of a recent biography of Collins. “There are two sides to it. She is often taken to be one of Childers’s great influences in being a staunch republican, which is blamed on her American background.

“But it sounds like Michael Foy has new information and has made an interesting find. If true, it was very well hidden.”

Another piece of Foy’s evidence is that Sir Hamar Greenwood, a British official who knew the identity of the spy, sent a copy of one of her reports to Lloyd George’s mistress, Frances Stevenson. Hinting that this was an Irish Mata Hari, he said the information was coming “straight from the cow”.

Childers took De Valera’s side in the civil war, but was captured by pro-Treaty forces at Glenalough House before he could use the small pistol Collins once gave him for personal protection. Sentenced to death for treason, he was executed.

Molly lived until 1964, and in 1973 their son Erskine Hamilton was elected president. He died in office a year later.

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