I agree that this information is correct, but it doesn't specifically address the term "civilian" that the OP was asking about.

@MichaelHall Geneva III, Art.4(6).

@Trish, OK. That says they are to be treated as a POW if captured. That doesn't answer the question, or relate to either this answer or mine. So what is your point in posting the reference?

@MichaelHall anyone under Art. 4 is considered a lawful combatant. Anyone not is either a civillian or an unlawful combatant. Since T falls under Art.4(6) he is an enemy combatant. See my answer.

@trish, there are civilian combatants, (guerrillas, resistance fighters) and military combatants (state sponsored, organized forces). I agree if you fight you are a combatant. But the question asked specifically about the word civilian. Find me a reference that says you somehow join the organized state military forces when you pick up a rifle and I will back off, but we are arguing about similar, yet very different terms here...

No, there are not "civillian Combattants": those are militia under Geneva III Art.4 A 1&2 or spontanously picking up arms under 6. Civillian and combattant are mutually exclusive due to Additional Protocol I, Article 50.

@trish, "Militia" is plural, and implies at least some level of organization. The question specifically stated "does not hold any official position in an armed group". This is about an individual engaging in the defense of his neighbor.

> Additional Protocol I to the Geneva convention, Art. 50: A civilian is any person who does not belong to one of the categories of persons referred to in Article 4 A (1), (2), (3) and (6) of the Third Convention

> Art. 4 A (6), the Third Geneva Convention (Geneva III). Article 4 - Prisoners of war A. Prisoners of war, in the sense of the present Convention, are persons belonging to one of the following categories, who have fallen into the power of the enemy: (6) Inhabitants of a non-occupied territory, who on the approach of the enemy spontaneously take up arms to resist the invading forces, without having had time to form themselves into regular armed units, provided they carry arms openly and respect the laws and customs of war.

@MichaelHall where does he not fall under Geneva III, Art. 4(6) and thus is not a civillian?

The Geneva Conventions are rather clear: there is no such thing as a civilian combatant. You can be either a combatant, or a civillian. Partisans, Guerillios and resistance fighters are all part of Geneva III, Art. 4(2)

@trish, I'm having a hard time finding the test of Protocol 1, article 50 that you referenced. Do you have a link handy?

Never mind, you posted it in the comment on my answer. You win! Thanks for engaging in a civil manner, and having the references to back your position.

@MichaelHall thanks for understanding - we might need a little cleanup after this moved to chat^^

@trish, I just deleted all my comments on the answer too. Thanks again for straightening me out. I learned something today, which is why I am here! ;)

@MichaelHall Geneva Convention and Law of War are complicated, no problem being wrong at times