When a bin-bag containing £100,000 was left on the doorstep of a former vicarage in York last year, the church, which still owned the property, handed it over to police.
But when an investigation found no evidence of where the money had come from, the church was told it could keep the cash: two and a half times its normal annual income. The money will go to support local community causes.
Most of us have found cash lying around at some time or other - though generally rather smaller amounts. But what's the procedure if you take it to police?
"Once you hand it in, we take names and details, and if after a certain amount of time [28 days] it hasn't been claimed, you can claim it for yourself," says a spokesperson for Thames Valley Police.
However, this doesn't always happen. When builder Steven Fletcher handed in nearly £18,000 that he'd found in a burnt-out flat he was renovating, he was less lucky than the York church. A High Court judge ruled that the money was probably derived from criminal activity, and confiscated it under the Proceeds of Crime Act. Fletcher didn't receive a penny.
A survey conducted by Alliance & Leicester a few years ago produced a surprising result. Only four in ten people said they'd bother handing a £100 find in to police, with five percent saying they'd donate it to charity. More than half said they'd simply keep the cash.
The Thames Valley Police spokesperson confirms that those finds that get reported do tend to be on the large side, indicating that most of us don't bother reporting small amounts, and just appreciate the windfall instead. But, he says, "Anecdotally, I've heard from station duty managers of people handing in £5 to £10."
People tend, understandably, to be more punctilious about returning money when there's some way of tracing the owner. Last September, Readers Digest tested the honesty of residents in 16 cities worldwide by dropping a wallet containing about £30 and a phone number.
Helsinki turned out to be the most honest city, with 11 out of 12 dropped wallets making their way back to the owner. Lisbon was worst: only one was returned, and that was handed in by a pair of Dutch visitors. London came ninth out of 16 for honesty, with finders returning five of the 12 wallets.
For many of us, though, our response to finding £30 would be very different depending on whether there's any way of tracing the owner or not. Indeed, the law says that a finder must take 'reasonable steps' to find the owner - which would certainly include calling the phone number in Readers Digest's lost wallets.
"It depends how much you find," says Keith Etherington, associate at Slater & Gordon. "The more you find, the more you're expected to do, and there are no hard and fast rules." In other words, you wouldn't be expected to trek to the police station to hand in a lost pound coin - but twenty thousand pounds would be a different matter.
But, says Etherington, "If you're following someone along in the street, you see them drop their wallet and you pick it up - or if you see a person drop £10 in a shop and you keep it, then you're stealing, because you know who it belongs to."
The same rules about making reasonable efforts apply to finding anything of value, and the rules about keeping unclaimed property are the same - with a few exceptions. If you find, say a mobile phone or laptop you shouldn't expect to get it back, even if it isn't claimed, because of data protection issues.
And when it comes to finding treasure, the situation's more complicated. As a rough guide, any gold or silver over 300 years old most be reported to the local coroner. If it's deemed to be treasure, it's offered for purchase to museums, with the finder sometimes receiving a reward; if no museum wants it, it's returned to the finder - although the landowner may have a claim.
It's probably better to be safe than sorry. In one extraordinary test case in 1965, a police officer who found a bag of rabbit food, intending to hand it in as lost property, failed to get round to it and kept it instead; he was initially found guilty of theft by finding, and only acquitted on appeal because the court ruled that he'd never intended to steal it.
And a couple who found a winning lottery ticket on the floor of a supermarket in 2009 found themselves convicted of fraud for cashing it in, and ordered to pay back half the £30,000 to the rightful owner. Michael and Amanda Stacey said they hadn't realised they'd done anything wrong, and many might sympathise; but legally, they should have reported it to Camelot.
"It's property, in the same sense as anything else, and things like that have a value," says Etherington. "If it's a winning ticket and you keep the money, then you're asking for trouble."
Have you ever found money on the street? What did you do? Please share your stories in the comments box below.
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