Am I allowed to use Krav Maga for any case of self-defense?
Of course you are, within the normal parameters. You will only use what you need with the amount of force required in order to defuse and escape from a situation. The amount of force that is considered "legal" will differ from jurisdiction to jurisdiction based on current law and precedent case law ...
Yes, arm triangles are legal provided you trap one of uke's arms with their head. According to the IJF Refereeing Seminar 2018:
An action like kata-sankaku (sankaku done with the arms) is allowed in a newaza situation.
Here are some examples of its use in international competition:
World U21 Championships 2015 (Jorre Verstraeten)
Jigoro Kano Cup Tokyo ...
How the heck can you walk in a ready stance down the street without the whole freaken place going 'ooooh, aaahhh'.
I was trained in hand-to-hand combat by the IDF, not by a school or embassy, so my perspective may be different than that commonly taught. But I do use the same approach on my home street as I do in Jenin. There are two types of people who will ...
Am I allowed to use Krav Maga for any case of self-defense? Even a threatening or grave suspicion.
You should never give this any concern in a real-life situation. You neutralize the attacker, and no more. If there are multiple attackers, you should be excessive on the first so that he will not return to the fight, but never do excessive harm to the last ...
Just to add to mattm's answer - the IJF has now codified its position in the current ruleset:
So in short, the following submissions are/aren't legal:
D'arce / Ungvari / Japanese necktie
Standing arm triangles
In German laws there is a term which could be translated as 'self-defense-excess'. The classical example is shooting children from your cherry tree in order to prevent them from stealing the cherries. That is forbidden in general (easy to understand).
In the special case that your excess happens out of asthenic affects (i. e. due to fear or terror), that ...