For someone who's got elite combat training there 3 levels of action in fight and self defence.

According to situation and person who's attacking or how many are there and what are motives they will make decisions fast in their brain what level of combat and self defence they use it.

1.just blocks and little power used not hurting anyone.
2. nothing serious but using the ufc boxing and mixed martial arts skills softer or stronger punches but nothing too damaging the body.
3.when nothing else don't work it's used in most critical situations....there will be no "nice fancy blocks or nice boxing punches" will be only deadly strikes to right parts of the body usually around neck and head area strikes to there will kill or make life long health damages for ever.
Level 3 used allmost never !!

They use numbers in the head once they decide what level they use they say this number in head the 1,2 or 3 once they say this their brain will set body and muscle memory the way that right level will be triggered.

One more thing, the law enforcement and police can't really reveal on public If level 3 been used, but it's been used not a lot and many people who been trying to use guns and a lot violance got killed or have life long health damage of level 3 been used against them a lot of them been involved off course extreme activities like kid napping extrortions and involved in terrorism activities.

Guess what even in the most extreme situations the level 2 is most used not the level 3

What i been told is that thank GOD that criminals terrorists and very bad people never faced those who got that kind of special skills,those people who mastering those skills many of them are body guards of countries leaders.