Does your art teach techniques that are potentially deadly?
If so, how do you know they will work if you've never killed anyone?

Any technique can be potentially deadly in my opinion. Its all just a question of placing a strike correctly. I am a karate practitioner primarily and know how dangerous straight karate strikes can be. They are not the most showy or impressive of techniques but the biggest aim of karate seems to be to get your attack from A to B as quickly and accurately as possible whilst generating as much power as possible. If I hit someone in the stomach they go down, if I hit them in the solar plexus, they go down and don't get up for a while. Hypothetically speaking, if I hit someone in a more sensitive area like the throat, neck or temple with the same amount of force from a normal punch, there is a high possibility that it will do permanent or even fatal damage. This is speaking only about punches as well. Many martial arts have some absolutely crazy techniques that could easily be fatal.

Wikipedia, in an article on karate speaks about the opinion about Gichin Funakoshi (Shotokan Karate):
"Funakoshi did not consider it unusual for a devotee to use Karate in a real physical confrontation no more than perhaps once in a lifetime. He stated that Karate practitioners must "never be easily drawn into a fight." It is understood that one blow from a real expert could mean death."

Good question!

How DO you practice a deadly technique?

If you understand anatomy and physiology it is not hard to figure out what is potentially lethal, and what isn't. If I strike you as hard as I can in the trachea with a tiger mouth strike I will more than likely crush your trachea. Unless someone in the area knows how to do a tracheotomy, or the EMTs get there soon enough, then you're dead. Is it 100% certain that my strike will do that damage? No, of course not. Under perfect conditions, yes, but Murphy likes to hang around anytime there is a fight brewing.

Ok maybe a bit fatuous but the techniques that could be deadly, which I have practiced recently have been:-

- Strangulation and choke holds.
- Any number of stick fighting strikes where the stick represents a machete.

As for how you know they would work, well its not hard to see that if you can apply a choke it could kill and if you hack someones neck with a machete that would be risky!

Otherwise we don’t train any techniques designed to cause fatal injuries.

Cheers
Nic

Tony is right, any technique hitting the right spot done the right way can be classified as deadly. Every knife-hand strike was designed to be deadly, don't delude yourself otherwise. And kicks were designed to break bones, a thrust kick to the chest can kill someone just as easily as a roundhouse kick to the head can kill someone. My way of practising deadly techniques is simply to the air, and never actually practise on a person. I'd rather just knock someone out then kill them, even if it is accidently.

I've never stabbed someone, but I'm pretty sure that if I did it enough, the opponent would die.

My art that I've practiced didn't, at least not to green belts. But I have studied a bit of anatomy-related strikes, and that is how it would be know. You figure an organ does a certain thing, and a certain other thing (say a knife-hand or perhaps a bullet) would interfere with it's functioning, and the result would be whatever happens when that organ ceases to function properly.