—"There must be an attack against you, or a third party whom you are trying to protect."
—"The attack must be against a person i.e. a threat to life and not property."
—"The attack must be about to start or must already have begun."
—"You cannot pre-emptively kill someone to stop an attack when that attack is not imminent or about to start, i.e. you cannot kill someone now to prevent an attack later."
—"Remember, if you can avoid the use of force you have a legal obligation to do so."
—"The law requires that if you can avoid a confrontation, you must take reasonable steps to do so e.g. by leaving the scene, if escape is possible. If you do not try to escape, when it is possible, it may be argued that you contributed towards the confrontation and therefore your actions in using force were not legally justifiable."
Source: International Training Academy's official handgun instruction manual required under South Africa's Firearm Control Act of 2000.