They do deserve it though. I think the law should be pretty clear on this. If someone breaks into your house and you kill them there should no repercussions.
In that case, would you like to come over to my house....
**BANG**
You're dead! Hit over the head with a baseball bat several times. I smash a window from the outside into the house, plant a little in the bottom of yours shoes to make it look like you've walked through it. Maybe cut you with a little of it and plant some blood on the window.
I've just killed a burglar and got away with it.