Moral question here.
Suppose there were frequent break-ins in your neighborhood. Somebody is going into houses when no one is home and cleaning them out. You notice a car whose driver you don't recognize, going up and down the street and slowing down when it passes your house. You believe your house will be next. The police don't seem interested in having a visible presence in your neighborhood.
On a weekend, you send your family to a relative's house. Park your car around back. Keep the lights off. Don't collect the newspaper or the mail. And sit silently in your dark house with your shotgun, waiting. When the thief breaks into your house, you shoot to kill. Then you turn your lights on and call the police. While you're waiting for the police to come, you pick up your newspaper and your mail.
Legally, you are allowed to use deadly force if you are in fear of your life. If someone breaks into your house it is usually assumed that you are, although it would probably be frowned upon if your housebreaker was shot in the back ... although not necessarily. So putting law aside, is this scenario morally OK?