Apple so the dog is on the deeds, is it? Pays the mortgage? No, didn't think so. The human aspect of property ownership is irrelevant. Neither the dog nor the cat takes it into consideration, it's an artificial construct that would not change the behaviour of either animal.
What matters is two conflicting sets of natural/happy environments: roaming vs killing. You can easily prevent a dog killing. You just choose not to, at the expense of the life (the LIFE) of the cat. Not its happiness, not its right to behave a certain way. Its life. And apparently that choice is okay.
Sucks to be a cat on MN.
Oh, and for the poster who asked, I have no pets, so it's not a choice I have to make. My daughter doesn't live with any animals who might harm her. The cats we had when I was growing up chose not to roam, were happy in the house/garden (nothing to stop them leaving, they just didn't) and not one of the four ever brought in a dead creature, nor did we find remains in the garden.
Dog people think dogs are marvellous, regardless of the evidence. I think all animals have their advantages and disadvantages, and a responsible person takes those into account. Doesn't just throw their hands up and say 'oh, that's dogs, what can you do?'
Imagine it were a toddler boy and a toddler girl, instead of a cat and a dog. Pre-verbal, or at least young enough that they don't 'get' explanations as to how certain behaviours are not acceptable.
The boy bites and seriously hurts the girl, because 'that's what boys do, you can't stop them, besides, it was in his own home which he has no actual ownership of and no concept of'
It's then the girl's fault for being near enough to the boy to allow herself to be bitten. So, that's okay, isn't it? The parents, knowing the boy is prone to biting, and choosing not to keep him away from the girl, or supervise, or teach him not to bite, are not responsible. Their choices are fine.
Jesus.