> Pursuing an attacker once the threat to yourself and family is clearly over is no longer self-defence.
Right, because having been chased once, criminals immediately become law-abiding citizens. No chance at all that they guy was running away to get some more buddies to come back and finish the job. I have no problem at all with someone who wants to ensure that crooks are available for the police to deal with.
Oh dear, a criminal getting a "permanent injury" from a victim. My heart is bleeding for him. Dude: you break the law, you're taking a chance. You'll get NO SYMPATHY if someone strikes back.
I assume the case in question is this one: http://blogs.telegraph.co.uk/news/timcollard/100020129/the-criminal-justice-system-is-just-not-cricket/
Munir Hussain found his family home in High Wycombe being burgled in a rather painful way. His wife and three children had been tied up and threatened with death. [emphasis mine] Munir himself, rather bravely, escaped by throwing a coffee table at the men, putting them to flight, and then chased after them. Thinking, understandably, that he might not himself be able to overpower and capture them, he armed himself with a cricket bat, and got hold of his brother Tokeer and, apparently, a couple of other people as well. There is no point in trying to apprehend criminals if you don't bring along the power to overcome them. [emphasis mine]
Don't know about you, but the last line makes a lot of sense to me.