Lord Justice Hoffmann, a Court of Appeal judge, and Lord Browne-Wilkinson, a law lord, abandoned years of training and allowed a woman's distress to get the better of them when they opened their doors in north London to a lady showing all the signs of middle-class respectability.
As the woman explained how she had had her purse stolen, and needed to pick up her daughter from a ballet lesson, they decided that her case was clear cut: no need to withdraw to consult with colleagues; they both dug deep and gave her the money - which they were promised would be returned the next day - as all good neighbours would.
Sir Leonard Hoffmann's wife was not amused. 'We swallowed the story. I wouldn't have given the money. Our daughter said immediately afterwards that we would never get it back,' she said, the family purse lighter by pounds 20.
Lord Browne-Wilkinson was not quite as gullible as his colleague, but he soon gave in when the woman burst into tears at his home in Camden.
He is also quids down, as are other well-meaning residents of Hampstead and Camden such as Jonathan Miller, the writer and director, Ben Whitaker, director of the Gulbenkian Foundation, and Caroline Garland, psychoanalyst at the Tavistock Clinic. Mr Whitaker, a former Hampstead Labour MP, said: 'You have to write it off as pounds 10 worth of life experience.'
The woman is practised in her art, having moved to her new patch from St John's Wood. Her story is always the same, either giving a fictitious address, or promising to call back the following day with the money.
She does so with a cheery: 'You don't know me, I've just moved into the street and I wave to you when you leave every morning.' She has now been reported to the police.