I find it disgusting that a case of obvious self defense even draws a question in a supposedly civilized country.
People do have the right to use reasonable force in self defence in the UK. This is not a licence to kill, however - the force used must be reasonable given the threat. Deadly force is justified if a person honestly believes themselves or another person to be at risk of death or serious injury. It is not justified unless they believe that.
I can kill a burglar in my home if I think he's likely to harm me. I can't if he's running away (as one example). Maybe the law shouldn't make these distinctions, but it is important to understand that there is a right to self defence.
Much more than disgusting. Further down in the story:
The right to defend one's property against intruders or burglars came to prominence in 1999 when farmer Tony Martin shot dead 16-year-old Fred Barras at his Norfolk home.
Barras and accomplice Brendon Fearon had disturbed Martin in the middle of the night.
Martin was jailed for life at Norwich Crown Court in April 2000 for murder, but his sentence was reduced by the Appeal Court to five years for manslaughter and he was released in 2003.
Fearon, who was wounded in the leg, was jailed for three years for conspiracy to burgle.