To escape liability, one who admits killing another in the name of self-defense bears the burden of proving: (1)
unlawful aggression on the part of the victim; (2)
reasonable necessity of the means employed to prevent or repel it; and (3)
lack of sufficient provocation on the part of the person claiming self-defense.[19]
The most important element in self-defense is
unlawful aggression – there can be no self-defense unless the victim first committed unlawful aggression against the person who resorted to self-defense.[20] Unlawful aggression presupposes an actual, sudden and unexpected attack or imminent danger thereof, not just a threatening or intimidating attitude.[21]