So if you find a tenner on the street and you don't hand it into the police station then you can be done for theft?
Just done some googling, it's called theft by finding, lots of news articles about people being charged with it.
http://www.metro.co.uk/news/820703-...finding-life-savings-in-charity-shop-suitcase



Does that make me a bad person. Not really imo.