The Code of honor:

Thou shalt not kill one who is taunting.
Thou shalt not kill one with a gun if they fight you with the sword or any melee.
Thou shalt not slay one with a medic on them.

Exceptions to the code:
If they taunt more than once, you may slay them.
If the taunt is a taunt kill, and it is used to slay you, you may slay them.

(you do not have to follow code)