The story has been updated:
http://news.bbc.co.uk/1/hi/england/sussex/8227517.stm
Quote:
“[The defendant] admitted hitting the dog with a garden hoe but denied criminal damage.
He said he did not mean to harm the dog, but was only trying to stop her from attacking his own elderly dalmatian...”
and
Quote:
“Magistrates decided that, as there were no witnesses to the incident, they could not prove that [the defendant] meant to harm Wurzel or was acting recklessly.
They added it was his right to defend his own dog and chickens on his own land.”
The problem here is that the article linked to by the OP was written when the prosecution had put its case, but the defence had yet to reply. The prosecution claim was that he had hit the dog with a hoe just for being in, and fouling, his garden. If that had been the case, I'd have been all in favour of coming down on him like the proverbial ton of bricks.
The defence claim was that the neighbour's dogs were attacking his own dog and his chickens at the time, and he was trying to stop that attack. That situation is rather different from the one presented in the first article.