I was at my partner's house when one of his housemates comes running up the stairs shouting that an intruder has just walked in and was following her up. By the time I had jumped out of bed and come around from the confusion, he was stood at the top of the stairs chanting all sorts of nonsense, with his hands in his pockets.
I am an army reservist and had travelled to my partner's house straight from drill night, which I have every Tuesday. As part of my equipment I have a utility knife with a non-fixed blade. I immediately grabbed this and phoned 999 (it took quite a while to get through to the police unfortunately, budget cuts eh...) whilst warning him off. I kept the knife withdrawn but hidden so as to not escalate the situation if he indeed was armed; he was clearly high as a kite and mentally disturbed.
He eventually high-tailed it out of the house and attacked the front door for a few moments and then left. The police arrived fairly quickly and I jumped in their car and we found him further up the street, he got nicked; job done.
As I understand the law in relation to self-defence against intruders in your home, it must be reasonable (which makes zero sense to me, even as somebody who has done a law degree - it just doesn't make sense, to me, that the law isn't black and white in this situation... but that's a discussion for another day.) Thankfully, the law is on the side of the defender in situations such as these, largely.
As I understand the law, you cannot own anything with an intended use as a weapon for self defence or otherwise. Though, what is the law in relation to equipping household items and even, in my case, a potentially deadly weapon just in case you've got to defend yourself? For all I know, this guy (who the police later confirmed to be mentally disturbed and under the influence) could have had a knife, a needle or anything else. In this case, I would have to have acted in-order to defend myself and others. So... what would then have been reasonable? If he withdrew a deadly weapon, would I then be entitled to use lethal force? Where would I stand in the eyes of the law? It is not owned for the purpose of being a weapon, I own it as it is part of my equipment and I had it with me as I had traveled from barracks to my partner's house.
I was absolutely not willing to wait and see what he had (if anything) or for something to happen before then choosing something to defend myself with. I see what I did as reasonable; to be awoken to screaming and shouting that someone has entered your home and is walking up the stairs, whilst chanting away to himself, throws up so many warning signs.