23.—(1) It shall be a defence to any action for damages against a person for the shooting of a dog, or to any charge arising out of the shooting of a dog, if the defendant proves that—

(a) the dog was shot when it was worrying, or was about to worry, livestock and that there were no other reasonable means of ending or preventing the worrying; or

(b) (i) the dog was a stray dog which was in the vicinity of a place where livestock had been injured or killed, and

(ii) the defendant reasonably believed that the dog had been involved in the injury or killing, and

(iii) there were no practicable means of seizing the dog or ascertaining to whom it belonged; and

(c) he was the person in charge of the livestock; and

(d) he notified within forty-eight hours the member in charge at the nearest Garda Station to the place where the dog was shot of the incident.

(2) The provisions of subsection (1) (a) and subsection (1) (b) (i) and (iii) of this section shall be deemed to have been satisfied if the defendant believed that those provisions had been satisfied and he had reasonable grounds for that belief.