It appears that UK residents do not have the right to defend themselves effectively in their house. This gentleman owned a shotgun legally, and used it for its intended purpose - to shoot vermin. What's the issue? (And for the love of Mike, why arrest the guy's wife? what did she do, hand him the shells?) The initial charge of "grievous bodily harm" in particular sounds optimistic, as both shot burglars were not seriously harmed.
Note that four burglars aged 25-35 have been arrested. In my opinion, any regular person is completely unable to defend themselves when outnumbered 4-1 by younger and stronger men - unless they have a firearm. Opening fire when four burglars break into your house in the dead of night, when your wife is there beside you, seems like a pretty proportionate response to me. This is not a case like Tony Martin where there was a certain amount of premeditation and firing when the burglars were running away from the property - this is reactive and proportionate.
As for the four burglars, I confidently predict that post-trial a long string of convictions for burglarious offences will emerge. No doubt they will return to their larcenous ways as soon as any legal confinement term has elapsed, as the Crown Prosecution Service confirm that burglars should be allowed to burgle free from interference.
It's just possible that the Crown Prosecution Service will decline to press this any further, after a couple of weeks of investigation and dragging this man and his wife through an expensive (in time and money) legal Hell. Frankly, though, I'm not optimistic - this looks like too easy a case for them to prosecute a law-abiding citizen. Perhaps they'll offer to drop the charge against his wife if he pleads guilty to a charge of Actual Bodily Harm. What I hope, though, if this case ever goes to court, is that the jury will not only throw out any charges against the shooter, but also find the prosecutor guilty of obnoxious, vindictive and anti-social prosecution and sentence him or her to four years hard labour. I can dream...
I'm not sure we can blame the arresting officers, as no doubt they are following strict arrest rules laid down by their police authority. However, we should hunt down the chair-warmers who a) thought up these rules and b) insisted they were followed for this particular case, and hold them to account. The police cannot police by consensus if they take actions like this.
Update: The folks at Inspector Gadget give some very useful background to why arrests are carried out in these circumstances. The point to watch here is to see whether the couple are actually charged, as opposed to merely arrested.