Maria Gatland, a Dubliner living in Surrey, clearly regrets the year she spent as a member of Sinn Fein and the IRA. Her case raises, in a particularly acute form, the question of when someone has the right to put their past behind them.

Gatland has suffered for her youthful republican affiliations. In the 1970s she was placed under a death threat and banned from entering Switzerland after admitting involvement in moving money for the purchase of weapons. “It was a painful and traumatic time for me and it took me many years to recover from it and closed many doors to me,” she told me last week.

Nowadays, she looks nothing like an IRA woman. Until last week she was a prominent Tory councillor who sat on Croydon council as the cabinet member for education. Gatland was outed after Dr Peter Latham referred to her as “councillor McGuire” (her maiden name) and wondered aloud whether, since she was Irish, she knew much about a book he had been reading about a year in the IRA.

“I didn’t know when I went into the meeting if it was definitely her or not,” said Latham, who was trying to force a vote on local education cuts. “Had she agreed to the ballots, I don’t think I would have mentioned anything about the book.”

It gave the Daily Mirror the sort of headline a Labour-leaning newspaper can usually but dream of: “Top Tory quits in IRA shame”. Gatland’s resignation from the party was demanded by Mike Fisher, the Conservative leader of the council, who gave the Croydon Advertiser an interview that reads, in places, like a script from Little Britain. “Councillor Gatland telephoned me this morning . . . She said she had been a member of the Provisional IRA and had been active at the time,” he said. “We do ask if they are a member of another party, but how can you check up if somebody has a history like this?”

He accused her of a betrayal of trust: the charge levelled by the IRA when Gatland published her kiss and tell account of her time with them in 1973. The Provos suspected she had been debriefed by British intelligence. Sean MacStiofain, the IRA chief of staff, who died in 2001, took a firmer line than Fisher: he warned Gatland that if she returned to Ireland she would face an IRA court martial and the penalty was likely to be death.

With MacStiofain, it was personal as well as political. McGuire’s book, To Take Arms, portrays him as a narrow-minded fanatic who was sniggered at and called “Mad Jack” behind his back. She even relates how he had secretly eaten steak while supposedly on hunger strike in prison.

All this may explain why McGuire decided not to publicise her past after she became a Tory matron in the shires. She did tell Mervyn Gatland, whom she married in 1976. He wanted to become a Tory councillor but died after a lung transplant in 2000 and she decided to enter politics in his place.

Like many young people in conflict situations, McGuire joined a terrorist group on the spur of the moment. A wealthy Dublin socialite from a respectable family, she phoned RTE with a request to be put in contact with Sean O Bradaigh, Sinn Fein’s director of publicity, after hearing him being interviewed.

After meeting her, O Bradaigh contacted MacStiofain, who recorded his impressions in Memoirs of a Revolutionary. “She was a university graduate, then aged about 23, and was supposed to be a linguist. It was felt that she might be able to contribute useful work.” She sensed he was a bit taken aback — “possibly he wasn’t expecting someone wearing hot pants to be interested in the Provisional IRA”.

Dave O’Connell (better known as Daithi O Conaill), a veteran of the 1950s campaign and a member of the Army Council, was more enthusiastic. He slept with her — and the pillow talk was fascinating. O’Connell talked of murdering MacStiofain and taking control of the IRA with her at his side.

A month after Bloody Sunday, he dispatched her to the north west, where Gatland spent days talking to local IRA members in Derry and Donegal before reporting back to O’Connell. The most sensational episode was an arms-buying expedition which degenerated into a binge of sex and drink conducted in European hotels at the IRA’s expense. The outcome was that 166 crates of bazookas, rocket launchers, grenades, rifles and ammunition, all paid for by the IRA, were seized at Schiphol airport in Amsterdam.

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