Senegalese troops crossed the border into The Gambia on 19 January, later halting their operation to give then President Yahya Jammeh more time to vacate office. They vowed to continue their intervention if he did not. Senegal was just one of a coalition of states to deploy forces on the country’s border. Was the action legal?

While Jammeh is an unpopular figure domestically, regionally and internationally, the legality of a military intervention in The Gambia is far from clear. But whether the legality or otherwise of military intervention ever makes a difference to potential interveners is another matter.

In essence, in Africa, as elsewhere, the key determinant on whether a military intervention takes place is political will rather than legality. Military intervention is sanctioned and executed by states. It is thus always a function of state interests rather than the objective, principled enforcement of law.

As a result, the history of military intervention shows inconsistency and, at times, hypocrisy.

Source of legality

The United Nations Security Council has the primary—some would say exclusive—authority to mandate military intervention. According to the UN Charter, force is legal in two circumstances:

• under Article 51, states may use force in self-defence; while
• under Chapter VII the council can authorise the use of force in response to a threat to international peace and security.

In the case of The Gambia, self-defence clearly does not apply. And whether the matter is a threat to international peace and security is obviously a matter of opinion. But this is a largely academic consideration.

In practice, since the end of the Cold War the Security Council has interpreted some internal crises as threats to international peace and security. For example, in 1994 it mandated the use of force in Haiti to restore the ousted president, Jean-Bertrand Aristide.

While many welcomed its more proactive approach, the council has implemented this new understanding of its Chapter VII powers in a highly inconsistent and obviously political way.

Under Article 52 the UN recognises a role for regional organisations in “the peaceful settlement of disputes”. Article 53 stipulates that regional organisations can “take enforcement action” but this must be done “with explicit authorisation by the Security Council”.

Thus, while regional organisations are legally empowered to take enforcement action, this does not diminish the primacy of the Security Council. In practice, however, it has proved willing to tolerate regional organisations acting without prior authorisation.

This happened in 1990, when the Economic Community of West African States Monitoring Group (ECOMOG) intervened in Liberia and again in 1997 when it intervened in Sierra Leone. The monitoring group is a multilateral armed force established by the Economic Community of West African States.

The primacy of the Security Council was challenged—to an extent—in 2003 by the African Union’s (AU) Constitutive Act. Article 4(h) of the Act recognises its right:

“… to intervene in a member state pursuant to a decision of the Assembly in respect of grave circumstances, namely: war crimes, genocide, and crimes against humanity.”

This led to debates as to whether the AU, in effect, declared itself an alternative source of authority to the Security Council. Again, however, this is a largely academic matter for two reasons.

First, the AU has never triggered the article.

Second, and of more importance in the case of The Gambia, there is no evidence —yet—that war crimes, genocide, and crimes against humanity have been committed. The threshold has therefore not been met.

But, in 2003, a “Protocol on Amendments to the Constitutive Act of the AU” was issued. This expanded the scope of Article 4(h) to include “a serious threat to legitimate order”. This would potentially apply in the case of The Gambia. But the protocols have not yet entered into force as two-thirds of the AU have yet to ratify them.

The final, and most controversial, basis on which military intervention can be legitimised is unilateral humanitarian intervention. This relates to situations where a state or group of states act without explicit UN authorisation to prevent or halt atrocities being perpetrated inside another state.

Perhaps the clearest example in recent years was NATO’s intervention in Kosovo in 1999. While the illegality of such intervention is relatively clear, some have argued that such action can at times be legitimate on moral or humanitarian grounds.

Tanzania’s intervention in Uganda in 1979, though technically illegal, was essentially tolerated—and in some quarters openly welcomed—given the nature of Idi Amin’s regime. Again, however, in the case of The Gambia, there is scant evidence of atrocity crimes. Thus this cannot be a basis on which an intervention is legitimised.

Not that the prospect of atrocity crimes in The Gambia can be ruled out. In June 2016 the UN Special Adviser on the Prevention of Genocide condemned Jammeh’s inflammatory comments about the Mandinka ethnic group as “irresponsible and extremely dangerous”. Many have accused him of a history of inciting ethnic division.

Thus, as it stands, it is not clear that military intervention in The Gambia would be legal. Yet one may well wonder whether this actually matters. History suggests that politics, rather than legal texts, determines both whether interventions take place, and how they are perceived by the international community

Law or politics?

In Africa, interventions to date illustrate that political calculations—particularly of powerful states—have always been key to the impetus for intervention.

This is true too of the regional response to intervention. This was particularly evident in Nigeria’s role within ECOMOG. In 1990, the monitoring group intervened in Liberia, in 1997 in Sierra Leone, and in 1999 in Guinea-Bissau.

The interventions in Liberia and Sierra Leone are generally deemed to have been a success. But the intervention in Guinea-Bissau—though initially key to preventing major loss of life—essentially ended in failure. Without the political will exercised by Nigeria, the interventions are unlikely to have occurred.

In this sense, military interventions have always been the function more of political calculations than determinations to act in defence of human rights or defend democracy. Indicatively, ECOMOG’s interventions highlighted fissures between Anglophone and Francophone states. Debates on the merits of military action have been largely divided along these lines.

Both ECOWAS and the African Union are coalitions of states. Previous attempts to create a genuinely trans-state political union in Africa have failed, and while the AU’s charter includes a provision for a standing army, this does not exist. Thus politics and national interests will, as ever, drive the response to The Gambia.

A robust and quick response to this crisis may well be legitimate. But it will invariably lead people to wonder why the intervening states were so keen to act swiftly in The Gambia, while similar resolve was not in evidence elsewhere.

Dr Aidan Hehir is a Reader in International Relations at the University of Westminster. He previously worked at the University of Limerick and the University of Sheffield.

This article was first published on The Conversation on 20 January 2017. It is republished with permission.