For those not familiar with the term "disparity of force," it refers to situations where the attacker is unarmed, but has such a physical advantage over the intended victim that if the attack continues it is likely to result in death or grave bodily harm to that victim. Elements creating disparity of force on the part of the attacker include a significant advantage of size and/or strength, known or obviously recognizable skill in unarmed combat, position of advantage (he has you in such a position that you can't fight back without a weapon), male attacking female in most cases, force of numbers, and able-bodied attacking the handicap, even if the handicap has been inflicted in the course of the initial assault.
As to elder attacked by younger, the disparity of force is determined by the latter -- that is, by the debilities associated with advanced age as opposed to chronological age by itself. Let's assume that the attacker is 25 years old, and his intended victim is 73. On the surface, it sounds like disparity of force. However, if the 25 year old is an anorexic 130 pound junkie and the 73 year old is Arnold Schwarzenneger, a disparity of force defense is unlikely to favor Arnold.
The disabilities often associated with advanced age are what will determine disparity of force: things like arthritis, osteoporosis, limited range of movement, reduced muscle mass and endurance, etc.
Not just age per se.
Disparity of force does not warrant a deadly force response in and of itself. The assailant must be close enough that the danger he presents is immediate, and there must be an element of manifest intent, sometimes known as "jeopardy," as well. When the three elements are simultaneously present they constitute "Ability, Opportunity, and Jeopardy" creating a situation of immediate danger of death or great bodily harm. It is this combination of circumstances that would justify lethal force in self-defense, all seen through the lens of what the Courts call "the totality of the circumstances."
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Thank you very much, you have explained that in a way that is very easily understood. I can see that age is only one aspect, something I expected but wasn’t sure about. That’s one reason I always carry pepper spray, especially when carrying a firearm.
Thanks again Mas.