At Sign of the Times, a high-end dress agency in Chelsea, a client is haggling over the price of an “as new” Hermès Birkin — but as she’s here to sell, she’s trying to drive the price up. She walks away to the tune of £4,000. “It’s all we could give her,” says the owner, Lorraine Fraser. “We have to make some profit.” According to Fraser, “people bring in expensive mistakes, or unwanted gifts from ex-boyfriends”. But reports of a new trend, whereby wives of wealthy bankers are spending on their husbands’ credit cards, only to resell the goods to stores like Fraser’s and pocket the cash, suggest that perhaps these expensive “mistakes” represent an emerging mini-industry in fashion laundering.

Syl Tang, a trend tracker at Hip Guide, says that, in New York, fashion laundering is rife among women concerned about their husbands’ diminishing earning power. As many marriages hit the recession rocks, “it’s an insurance policy”, she says. One personal shopper told Tang that she could predict when a woman was about to leave her husband by her purchases — “investment” pieces like the Hermès Birkin, and labels such as Chanel and YSL. New figures show that, astoundingly, sales of luxury accessories were up 40% in Selfridges in February. James Servini, the accessories buying manager, says: “It’s the big boys — Chanel, Prada and Louis Vuitton — that are doing well.” Brands that have a high resale value, then.

He also cites a trend among the ladies who lunch, who are “shopping less frequently, but spending more”. Are these canny women stockpiling for leaner times ahead? Ann Ison, a partner in family law at Hughes Fowler Carruthers, works on the big-money divorce circuit. “One woman was spending vast sums on her husband’s cards, post proceedings,” she says. “She even stocked up on airline tickets, for use in the future.” Another client was spending “an unusual amount on petrol”, filling up her friends’ cars in exchange for cash, perhaps.

Legally, a woman is perfectly within her rights to dip into the marital pot, but what are the moral implications? For Elizabeth Ford, co-author of the new book Smart Girls Marry Money, it’s a no-brainer. “We don’t judge his morals for choosing a woman for her looks, so what’s wrong with choosing a man for his money, and then using it?” Fashion laundering “is simply a redistribution of the assets in the marriage”. Indeed.

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