South Africa’s minister of justice and correctional services, Michael Masutha, in Pretoria on Oct. 21, said South Africa will soon submit a bill in parliament to withdraw from the International Criminal Court, making the country the second this week, after Burundi, to move to leave the tribunal. (AP)

Last week, Burundi’s parliament voted to leave the International Criminal Court. It seemed clear that an official withdrawal, which requires sending formal notice to the U.N. secretary general, was imminent. For many commentators, the only question was whether the move heralded a long-threatened mass walkout by African countries or whether Burundi’s increasingly poor reputation in the international community would keep other governments from following its example. Speculation centered on Kenya, whose parliament adopted a similar measure in 2013, Namibia, where legislators did the same in 2015, and even Uganda, whose president has recently been very critical of the court. But in a shocking development, South Africa beat Burundi to the punch Wednesday, becoming the first member state to begin a formal withdrawal from the ICC.

If the likelihood that Burundi would inspire copycat withdrawals seemed limited by that country’s slide toward pariah status, South Africa is another story entirely. A leader in the region, as well as a strong proponent of international justice, South Africa was an early and vocal supporter of the ICC. And while Burundi’s motivations for withdrawal are clearly rooted in the current regime’s short-term domestic political interests, South Africa’s are murkier and potentially far more damaging to the long-term prospects of the court.

Why Burundi is leaving the court

Burundi has been embroiled in a violent political crisis since April 2015, when President Pierre Nkurunziza announced he would seek a controversial third term in office. Over the past 17 months, the ruling party has repeatedly batted back attempts by regional and international bodies to intervene. When the ICC’s chief prosecutor launched a preliminary examination into the ongoing political violence in Burundi this past April, human rights advocates welcomed the news, hoping that the ICC’s engagement would restrain the country’s leaders. But the violations — torture, extrajudicial executions and disappearances — have continued.

The government has evaded the United Nations’ attempts to send in police observers, claiming its own security forces are sufficiently in control. While the United States, the European Union and other East African governments have urged full participation in a regionally sponsored peace process, the Burundian government pointed to its internal dialogue commission and human rights inquiries as the appropriate avenues to achieve reform and accountability. And when the African Union authorized the deployment of a prevention and protection force to protect civilians in December 2015, Nkurunziza promptly rejected it, saying that outside troops were unnecessary and that deploying them would amount to an attack on Burundian soil.

But despite Burundi’s best efforts to prevent human rights observers from visiting the country, a U.N.-sponsored independent investigation found state agents responsible for “gross human rights violations,” in some instances amounting to “crimes against humanity.” These are the types of crimes the ICC could prosecute. Just a few weeks after the publication of this report, Burundi declared the human rights experts who authored the report personas non grata and put forward the plan to leave the ICC.

Burundi is certainly free to leave the court. Membership in the ICC is voluntary and limited to those states that have signed and ratified its founding treaty, the Rome Statute. Burundi did this in 2004, which is why the court’s prosecutor was able to act in April. If the preliminary Burundi examination proceeds to a full ICC investigation, it will be the court’s 11th — the 10th looking at violence in Africa. That regional focus is Burundi’s purported justification for the withdrawal. The ICC, it claims, is “violating the rights of Africans.”

Burundi’s government is not the first to make this allegation. The lack of diversity in the ICC’s charge list has been a point of contention for years. On multiple occasions, members of the African Union have lobbied for the organization to stage a mass walkout. But in fact the seeming bias is hardly the court’s doing. Not only is the organization consent-based (meaning the prosecutor can’t investigate crimes by nonmember states such as Syria without a Security Council referral), but most cases arrive before the court by the request of the state involved. The governments of Uganda, Congo, the Central African Republic and Mali all asked the ICC to investigate violence occurring in their territories. The list of countries where the prosecutor’s office has opened preliminary examinations on its own initiative is significantly more diverse; along with Burundi, it includes Afghanistan, Colombia, Guinea, Honduras, Iraq, Nigeria, Palestine, South Korea, Ukraine and Venezuela.

But if Burundi’s justification for its threatened withdrawal is weak, its actions are no surprise. They are part and parcel of its overall strategy of retreating from international institutions that monitor and impose penalties for human rights abuses. And while the withdrawal probably wouldn’t put a stop to the pending investigation, it does send a clear signal that the country’s leaders do not intend to be deterred from further violence against civilians.

Why South Africa is different

Unlike Burundi, South Africa has never been under investigation by the ICC. It has historically had a strong relationship with the court and was a prominent resister of the initial calls for an A.U. walkout. Things began to sour in 2015, when South Africa allowed Sudanese President Omar Hassan al-Bashir to freely enter and exit the country for an A.U. meeting, despite the ICC warrant for his arrest, which South Africa was obligated to execute as a member of the court. The failure to detain Bashir had domestic political fallout, with South African courts ruling that the government had violated not only violated its international legal obligations but also its own domestic law. It also seriously harmed the country’s international reputation.

In the aftermath of the Bashir contretemps, South African officials threatened to leave the ICC. Nevertheless, the move Wednesday comes as a surprise. South Africa’s purported justification for the withdrawal nods at the peace-vs.-justice debate: “The Republic of South Africa has found that its obligations with respect to the peaceful resolution of conflicts at times are incompatible with the interpretation given by the International Criminal Court of obligations contained in the Rome Statute.” But a different logic may be operating: As anti-ICC sentiments have hardened within the A.U., South Africa has struggled to balance its role as a regional leader with its ambitions as an emerging global power. One read of the situation is that the withdrawal is less about South Africa’s relationship with the court than it is about its view of itself vis-à-vis the rest of the continent. If, in fact, a mass walkout is imminent, South Africa would prefer to lead the movement rather than follow others.

Burundi’s exit underscores the limits of the ICC’s effectiveness. One of the primary justifications for the court’s existence is that it might deter mass atrocities, in the world at large and in the specific conflicts in which it intervenes. But the evidence on the court’s impact is mixed, and the incentives actors face are complex. In Burundi, the effect of nearly two years of focused international engagement seems to have been not to prevent further violence against civilians but to inspire Burundi’s leaders to hide the violations better, while also distancing themselves from the international community.

These developments underscore the challenge for the international community of preventing atrocity crimes, even when the warning signs are unmistakable and an international criminal court is investigating. But the Burundis of the world were always going to be hard cases for the ICC. The incentives to commit atrocities are powerful, and we expect poorer cooperation with international institutions when it violates states’ clear interests. South Africa’s departure is far more troubling. It should be an easy case for ICC cooperation — a country that feels little threat of being investigated by the court and has a tradition of strong engagement with the international community and leadership on peace and justice issues. Its decision to withdraw sets a far more palatable precedent for other ICC skeptics to follow and makes a mass exodus much more likely.

Kate Cronin-Furman is a postdoctoral research fellow in the International Security Program at the Harvard Kennedy School’s Belfer Center for Science and International Affairs. Stephanie Schwartz is a PhD candidate in political science at Columbia University.