Being a sort-of pacifist and all that, I would never kill somebody. But some people just seem to invite it. Like the clueless geek I saw at my favorite coffeehouse, who had somehow managed to get a girl to go on a date with him, and spent a good 30 minutes or so enthusiastically describing nearly every scene of Star Wars: The Phantom Menace. Luckily, I left before he got to Linux. Why his date didn't just jump up and strangle him, I'll never know. Possibly she had been lulled into some kind of strange trance--her eyes were glazed over. Gamers who recount every dice roll of gaming sessions qualify, too, as do people who play with their keys (or with a laser pointer, God forbid) when someone around them has a migraine.

The only good response to these people, and telemarketers, runs along the lines of "Ka-click!" or, as Zorak would say, "Die die die, die die die, die DIE die die die!"

Unfortunately I never was that good at picking the appropriate response...

For a homicide to be considered justifiable in the eyes of the law the situation must be proven to fulfill certain requisites. These requisites vary from country to country but mainly revolve around establishing that there was a clear and present danger to one's life or limb or to that of an innocent person, and the only way to have stopped this danger was to inflict deadly force.

These are what constitutes clear and present danger:

• The attacker's ability to inflict bodily harm.
• A plausible motive for the attacker to inflict bodily harm.
• The lack of alternatives or obvious impossibility of withdrawal or retreat.

These are just the bare basics, if ever confronted with a threat and you are mentally weighing if it is a shoot or no-shoot situation, keep in mind the preceding requisites. Fail to prove any single one of these and you can count on being charged with manslaughter or even murder and getting your ass hauled off to jail.

Notice that this only covers threat to one's life or limb, the threat to property is a different thing altogether. In some countries, there is a "castle doctrine" saying that anybody who breaks and enters into your property can be legally met with deadly force.

Though this does somehow encourage people to include their property in the things they are allowed to protect with deadly force, it is, in general, not justifiable to shoot somebody who snatched something from you and is now running away. Exit wounds in the frontal area of the person does not make for a very good case unfortunately.

Do not take this as legal advice as I am not a lawyer.