A former student of mine got into a scrape this past week where he was attacked by someone else and was forced to use his training to defend himself. He was able to escape unscathed whilst causing only minimal damage to his attacker. Afterwards he asked me if what he did was alright. Although what he asked me would at first seem to be one question, I viewed it as three questions. The first is was it alright morally, the second legally, and the third martially.
I don’t intend here to get into the specifics of what happened, but instead to look at how these three questions are answered in regards to any fight you might get yourself into.
Assuming you’ve taken any sort of formal martial arts classes, you’ve likely been lectured on how what you are learning ought only be used for good, how you should never start a fight, how this is a last resort, etc.. Unless you are being taught martial arts in a military context (where you are literally being trained to kill people) this should sound familiar to you. If it doesn’t, then I advise you get a different teacher since the purely physical side of martial arts is not something that should ever go unaccompanied without lessons in morality.
In the first two contexts (moral and legal), there are different levels of allowable force depending upon the situation. What you are permitted to do against someone twice your size with a gun is much different than what you are permitted to do against someone your own size with just their bare hands. Although I often advocate for the most peaceful solution, I do not believe in absolute pacifism and as a result see it as morally permissible to cause injury to your attacker if you are in sufficient danger. It is my suggestion that you attempt to cause as little damage as possible to your opponent, you should thus aim for the disarm and the joint lock as opposed to bone breaks or eye gouges, however your priority should be survival. If your only way to run away is by breaking your opponent’s knee, then you should do what you must. A situation like this where you might be forced to cause severe damage is easier to think of in a case where your attacker is not alone and thus holding them in a lock would be ill-advised.
By attacking you, the aggressor has made it morally permissible for you to retaliate. your response should never be greater than what your opponent was ready to do to you. This means that if someone swings at you, you would not be justified in shooting them in the face. The situation here becomes less clear when the two sides are mismatched. Assuming all other things are equal, someone being attacked by someone twice their size would find a wider array of options to be morally permissible than if the situation was reversed since force equals mass times acceleration, which means that more mass equal more force and more force equals more damage. In certain situations this would mean that someone would be justified in pulling a weapon on an attacker who either has a less dangerous weapon (such as someone pulling a gun on someone attacking with a stick) or is unarmed. Pepper spray and tasers are the easiest examples of this even though I wouldn’t advocate on the use of either in a self-defense situation (pepper spray can blow back at you and taser tase you as well if you are in contact with the person attacking you).
What is permissible in the legal context is generally similar to what is permissible in the moral context, with a few differences. Depending on who you are, what you may or may not be allowed to do can change. David R. Packer wrote a wonderful article about what you are and are not allowed to do depending on the situation if you are a security guard in Canada which can be found here http://boxwrestlefence.com/blog/2012/09/12/structures-of-violence/. As someone whose job does not require you to know the intricacies of self-defense law, you will likely be given more leeway than someone in Packer’s position. This does not mean though that everything is necessarily straightforward. In certain states it is even legal for you to kill someone for “invading your home” (http://www.nytimes.com/1990/06/01/us/colorado-journal-make-my-day-more-than-a-threat.html).
Laws regarding levels of allowable force are not a new invention. This summer I had a conversation with Christian Tobler who is an expert in medieval and European German martial arts where he told me at which points you were allowed to use different parts of a sword. For lesser offenses you could use the pommel or the flat of the blade. In cases where you were at a larger risk of being seriously inured, you were legally allowed to use the sharp part of the blade. Then, only in the most serious cases, where you allowed to use to point of the sword. The reasoning behind this is that although you could theoretically kill someone with the pommel, the sharp side or the point, they each pose varying degrees of risk. Were you to get hit by the pommel, you might walk away with some bruised ribs but unless you were pummeled (yes, that’s where that word comes from) in the head, your chances of survival were pretty good. The sharp part was even more dangerous, but we’ve all been cut before and survived and most of your vital parts aren’t very close to the outside of your body and likely to get cut. It is also important to note that since this was during a little ice age, it was generally much colder out and people in the area would often walk around with padded jackets on, making it much harder to become mortally wounded from a slash. The point of a sword, however, will go straight through fabric with very little force and only has to go about the thickness of three fingers in to be lethal.
Finally there is the martial side of the issue. This is the purely strategic side. What do you do to stay alive? Out of jail? Not have their friends come after you for revenge? The first part here is the bulk of what you will learn in a martial arts class, what you need to do to defend yourself sufficiently so that you can walk away at the end of the day without sustaining any major injuries. The second part is less an issue of what the law advises and more of where the law draws the line and will punish you. It is important to remember here that a court will likely side with a small woman who caused her attacker to sustain serious injuries than it would for a large man to do the same. The last question, although least often addressed, might be the most important one depending on your situation. If their friends are there can you dispatch of the attacker that will cause their friends to laugh without finding reason to join in the fight? Will their family members spend their entire lives searching you out for killing your attacker? Do they have connections to very dangerous, well organized people? These are all important things to consider.
Throughout this entire post, I have only addressed scenarios wherein you are clearly the being attacked. My thoughts on what is and what is not justified when intervening on behalf of someone else will be for another post.