There has been a lot of attention in the press and blogosphere about the worrisome situation in Libya, the (in)adequacy of the United States' and United Nations' response thereto, and the Security Council's unanimous referral of the situation to the International Criminal Court via Resolution 1970 on February 26, 2011. (See our prior coverage here). On March 2, 2011, the ICC Prosecutor announced that he had opened his investigation into potential crimes committed in Libya (see his press conference here). The President of the ICC, Judge Sang-Hyun Song (S. Korea), thereafter assigned the situation to Pre-Trial Chamber I.
In undertaking his investigation into international crimes committed since February 15th, the

War crimes may also have been committed, depending on whether the situation in eastern Libya or elsewhere rises to the level of armed conflict.Common Article 3, whose prohibitions are listed

All this implies that the heightened threshold of Protocol II, which also governs non-international armed conflicts and whose prohibitions may be prosecuted as war crimes pursuant to Article 8(2)(e) of the ICC Statute, may also be satisfied. That treaty becomes applicable when there is a non-international armed conflict
which take place in the territory of a High Contracting Party between its armed forces and dissident armed forces or other organized armed groups which, under responsible command, exercise such control over a part of its territory as to enable them to carry out sustained and concerted military operations and to implement this Protocol.
of internal disturbances and tensions, such as riots, isolated and sporadic acts of violence and other acts of a similar nature, as not being armed conflicts.
The crime of aggression is not immediately implicated in the Libyan situation. For one, the aggression amendments will not come into force until 2017 at the earliest. Moreover, the definition of the crime does not envision the act of aggression being committed by or against non-state actors that are not linked to a state. Nonetheless, the crime of aggression may bear on responses by the international community to the crisis in Libya.
Indeed, military options are not off the table, according to recent comments by President Obama and other world leaders. In particular, it has been proposed that the international community—or some subset thereof—should impose a no-fly zone over the country in an effort to prevent Libya's increasingly erratic and vicious leader from committing further violence against his own people. The Gulf Cooperation Council and Arab Leaguereportedly support such a measure as do several vocal members of Congress. France and Britain are working on a draft Security Council resolution that would authorize such a response, although it is unclear if Russia and China would support this measure, which sounds of military intervention.
This raises the prospects that a group of states, such as NATO or some other coalition of the willing, might move forward without explicit Council approval. This is exactly the kind of scenario that worries detractors of the codification of the crime of aggression in the ICC Statute.
The imposition of a no-fly zone without prior Council approval might run afoul of the prohibition of aggression as it has been defined in the aggression amendments. Article 8bis(2) of the amendments defines “act of aggression” broadly as
the use of armed force by a State against the sovereignty, territorial integrity or political independence of another State...
a) The invasion or attack by the armed forces of a State of the territory of another State ...;
b) Bombardment by the armed forces of a State against the territory of another State or the use of any weapons by a State against the territory of another State; ...
d) An attack by the armed forces of a State on the land, sea or air forces, or marine and air fleets of another State...
- the prosecutor (exercising prosecutorial discretion),
- the Pre-Trial Division (which would need to approve aggression charges), and
- the Security Council (which also acts as a filter to aggression charges and can defer prosecutions for a renewable period of a year).