This section examines the duration of time that IHL is applicable for.
There are no easy answers to this question.
If, for example, we look at treaty rules we find a lot of room for disagreement.
IHL norms are almost inexistent with respect to NIACs; they do not use a coherent terminology
regarding IACs and they provide for different solutions concerning the law of occupation.
However, we may venture to formulate a general principle and some general remarks.
The most important, overarching principle may be expressed as follows:
since the triggering of IHL is dependent
upon the factual occurrence of an objective situation, an armed conflict
or a situation of occupation, it seems logical that IHL will cease to apply
when those situations will cease.
So, it does not matter whether a cease-fire, armistice, peace agreement
or any other formal agreement has been concluded.
What is crucial is that the armed conflict or the situation of occupation has ended.
Formal agreements may only serve as evidence of the cessation of armed conflict.
Three general remarks must also be added.
Firstly, IHL, and law in general,
must have a degree of resilience in the face of rapid changes.
Armed conflicts may disappear and quickly resume.
The application of IHL must therefore be characterized by some degree of stability in order to provide
legal predictability and security to all of its addressees.
As stated by the ICTY, "[o]nce the law of armed conflict has become applicable,
one should not lightly conclude that its applicability ceases.
Otherwise, the participants in an armed conflict may find themselves in a revolving door between
applicability and non-applicability, leading to a considerable degree of legal uncertainty
and confusion".
In that sense, an armed conflict does not cease as soon as the threshold of its application
is no longer met.
Its end is not a mirror of its coming into existence, to the extent that the conditions
for its cessation must be stricter than the conditions for its starting.
Once the existence of an armed conflict has been established, the armed conflict can only
be considered to have ended if the conflict has ceased with a sufficient degree of permanence.
Secondly, certain IHL norms continue to apply even after the end of the armed conflict.
There are first a small number of norms that apply continuously, even in times of peace.
These include, for example, the obligation to disseminate IHL
or to search for and prosecute war criminals.
There are also IHL norms which apply in times of armed conflict but which do not cease
to apply when the armed conflict ends.
These are the norms protecting the persons who have been detained.
Such protection is applicable until those persons have been released,
and in case of IACs, repatriated to their country of origin or re-established in another country.
Thirdly, more generally, as a matter of international law, certain IHL norms may also cease to apply
in the event that the state in question withdraws from IHL treaties.
This has never occurred and if a State were to withdraw from IHL treaties during an armed conflict,
it will still be bound by those treaties during that conflict and will remain
bound by all IHL customary norms.
