Hello Mike,

What we do not want to see is "legal battles on how to understand one word that has several meanings and various translations." Nobody is going to be looking up variant legalisms in the middle of a firefight.
Part from being the devils advocate (in a white suite of the stupid angel of humanitarian laws), I am also a practical man with boots on the field and I do agree with you on the fact that GC were not written to have legal battle on one word during operations.

Unfortunately, those legalisms (as applied to the gray areas) become personally important to combatants if they find themselves being prosecuted before the ICC, before a domestic court (in lieu of the ICC, as the Australian spokesperson said), or before a military court, because they chose a different interpretation of a legalism, or did not know that legalism existed.
That’s why, in my opinion, it is needed to have a clear understanding of GC and Hague Convention interpretation by your commandment and legal body before. And that’s also the challenge of everyone involve: take the right decision at a moment you have too many other things to think of. (And I support you 200% on that).

Pink and cheesy understanding would define the black area as: during combat and the white one any times everyone stopped firing… This also has to be put in regard with the type of engagement those rules were designed for: regular wars between 2 conventional armies battling in open ground involving a large number of combatants… The 1st and 2nd WW battle type.

We do agree that it does not apply to most of irregular engagements.
Now the question of pursuit is important as in a court, it will be difficult to put in balance a military objective against a one man life, especially in a civilian court. (Well, I know some military judge who can be harsher than civilian judges…)

One could introduce both legalism and dogmatism into the scope of the clause "... particularly after an engagement ..." ("... notamment après un engagement ...") - that is, when does an engagement end ?

I doubt that anyone would contend that it ends when the objective is taken and firing dies down or stops, and contact is broken. At that point, the primary circumstances are what the enemy will do - e.g., some "maybes": (1) enemy counterattacks (requiring your prompt reorganization and consolidation); (2) enemy occupies a new fighting position (should the unit advance to attack this new objective); (3) enemy retreats (should the unit pursue). Those post-contact actions will interfere to a greater or lesser extent with care of the wounded.
There has been some legal decision make by the TIPY on what a conflict is and what the “duration/life time” of a conflict is. Have to look for details. The Karadzic trial in particular if I do not mistake.

The "circumstances" in irregular warfare are difficult, especially where the irregular force sets up a situation (e.g., involving wounded as one example) believing that the regular forces' probable application of its rules will be to the regulars' disadvantage.
Also, the rules are made for to mitigate the sufferings and avoid excessive use of violence. If the military necessity is taken in account, it is not an argument to pass over the obligations to the wounded.
I also do believe that the interpretation of the necessity VS obligation will differ from country to country and from court to court.
As example, I will use the Nuremberg case used by Michael Walzer in just and injust wars (sorry I do not have the book with me so it is from the top of my mind). In his example, the Allies accused the German navy to have assassinated and not rescued sailors. It appears that the German navy started to rescue the Allies sailors but when the Allies forces arrived on the spot, they attacked the German. (to make the story short)
The court found that it was the Allies who were in fault (and the German not guilty by the way) for having attacked while opponent was conducting a rescue mission.

Does that mean that you have to put you self in danger under the « protection » of a rescue/humanitarian mission? Definitively not. (That’s the job of the stupid relief workers; my job to put you in danger because I did exactly that and now I am in deep #### and need armed rescue )

To come back to our context, the point is: you have an obligation to act accordingly to the rules.
- You cannot attack opponent when they do conduct a “rescue” mission (Many comments from French troops in Astan on the fact that we let the Taleb go with their dead while they do not let us take care of our wounded).
- You have to provide relief and aid to wounded opponent as soon as possible.
- Primary responsibility to assist wounded falls under each side: you take care of your wounded, I take care of mine. The GC bottom line is just: if I find one of yours wounded, I take him prisoner and I heal him.

Now, you have crushed the enemy and they are fleeing… What is left is wounded they did not take with them. Well… Hard to said. Will very much depends on you assets, your capacity to conduct your mission, the objective of your mission, your opponent capacities…
I do also believe that in such a case, you take orders from your commandment. They are the ones qualified to determine if you keep on your mission or you have to stop. SOP for such situations should be issued before as well as what to do with the wounded.

Will take time to look at your synopsis in details.

I do also agree with JMA and hope it is done for that reason:
One thing for sure is that Semrau if he had his time over again would not do what he did. And I guess his prosecution is more to send a message to the rank and file of the Canadian army than to crucify Semrau.
It is important for the regular forces to also show that they do play by the rules (for the public ad the enemy) and are not affraid of taking the black sheep out of their ranks (with all respect for Semrau that I do not know personnaly).