Supposing a masked man who was unarmed broke in to your house in the middle of the night and was stealing your iPAD or laptop. You warned him to leave and were carrying a machete but he wouldn't leave, however he wouldn't attack you either. Would you be allowed to use the machete against him? What about if he came to attack you? Could you then?
This is a completely hypothetical situation. I do not own and have never owned a machete or any weapon!
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Self defence in the UK?