[TimTheTinker]

My father-in-law (from the US) always carries a small utility/hunting knife, which he packed in his checked luggage when taking a leisure trip to England.

I believe it was at a museum or another public attraction that a police officer saw the knife in its holder on his belt, stopped him, demanded he surrender the knife, and told him he'd be arrested if he didn't.

He was very upset - he'd had that knife for decades.