I'm not sure I'm clear on your arguments. You said that in your state proportionality doesn't matter in the eyes of the law, but then you gave examples of situations where they were enforcing a proportionality doctrine in your state. And you said at the start that you thought proportionality was the right approach, but at the end that you think we need to stop using proportionality as the criteria. Maybe spell out how you think it should work?
As far as I know, proportional response is the doctrine in every state, but yeah, as you point out, your response can either be proportionate to the battery they inflicted on you (what you're calling equal is really 'proportional'), or proportionate to the threat to your safety (what you're calling 'necessary'. AKA self defense).
Self defense is kind of a different thing than we've been talking about, but related. If you have good reason to believe that somebody is about to do something really dangerous towards you, you have the right to stop with whatever force is required to stop them. Then there are limits on that that do vary by states. In most states if not all, you are required by law to opt to run away before you use deadly force if that option is available to you for example- an affirmative defense of "self defense" in a homicide trial requires in most states that you show that it was your only option left to save your own life or limb. In most states you don't have to run away if you're in your own home. In most states there is some kind of limit on how severe your response can be given the threat- you can't kill somebody just to stop them from slapping you or something. Generally most states won't allow people to use deadly force to protect property except, in some states, if you're in your own home.
Ok, perhaps I wasn't entirely clear. Some of this depends on terminology and how you use it. As an ex-cop, I don't normally use the term "proportional force". In my state, the legal term is "reasonable and necessary force", and it is situation-dependent.
Proportional force implies that if you punch me once, I can punch you back once. It might also imply that if you're a 90 pound woman and you're punching me, that my "proportionate" responses are very limited. You might punch me in the face ten times and not leave a mark. Contrariwise, anything I do to you might leave a mark... and who has the noticeable bruises is often the deciding factor in who goes to jail. This isn't theoretical, I'm going by previous experience in LE.
In my state, "reasonable and necessary" implies that you may use such force as is necessary to STOP the attack. A certain proportionality is implied, but it isn't a strict standard but rather a
situational standard.
Also, in my state there is no duty to retreat before using deadly force, in most circumstances.
Now, you say that self-defense is different than what we're talking about. I would assert that in many cases it isn't different, or at least should not be. If you as a woman assault your man, he is defending himself if he reacts to your attack with force of his own. Granted that it should not be an inordinately greater level of force, but in many cases what we end up with is the man being arrested and charged for defending himself, because he grabbed the woman's arms in an attempt to prevent her from punching him and left bruises with his grip. In some cases she punches him and he punches her back, or slaps her... his blow leaves a readily visible mark, her's not so much, HE gets arrested.
I'm not sure what the solution is, since frankly in most cases the police arrive after the fact, there is no reliable 3rd-party witness, everybody is telling a different story, there is screaming and crying, etc. Unraveling who did what to whom is difficult. This is one reason a lot of departments are going with a policy of just arresting everybody involved and letting a judge sort it out later.
But at any rate, my point is that being a woman doesn't entitle you to hit a man and get away with it. Furthermore, while a "proportionate response" might be more "fair", that is a mighty fine distinction to expect someone to make in the middle of a very heated situation, when you've resorted to initiating violence against a man. It just isn't a good idea; he may very well hurt you badly without really meaning to, because you "activated his fight-reactions" by riling him up and then hitting him first.
I'm not speaking theoretically, as I've said. I should also note that I have personal experience, as my first wife (only wife actually) was violently abusive. I never hit her back because of my upbringing: the idea of striking a woman was most repugnant to me. It is probably wise that I did so, since I was able to prosecute her for CDV, get custody of our child, and keep the house. Had I struck her back, she would most likely have been seriously injured, I would have gone to jail and been charged and probably convicted, and she would have walked away with a child she couldn't take care of and property she didn't deserve.
Such a level of restraint in the face of severe verbal, emotional and physical abuse, including an attempt to kill me, is most difficult. Many men do not have that level of self-control. The single biggest point I am attempting to make is this: if you initiate violence against your man, you are being the abuser and putting yourself in a situation where you may be seriously injured, and if you do this it is MOSTLY your OWN fault. Most halfway-decent men won't hit a woman under most circumstances, but if you infuriate him and then resort to initiating violence, he may lose control.
In short, don't.
G.