You find a well used and sharpened kitchen knife in an alleyway on a housing estate, take it home and report it to the police. They log it, give you a reference number, tell you to bag it up and take it to the police station.

When you get to the police station do they …

The answer, of course, is throw it in the knife amnesty bin. I mean, why would the police want to see if a known criminal has been walking around a housing estate with a knife? That could lead to all sorts of paperwork …