Women in the town of Mweso, Congo, walk past a convoy from the U.N. peacekeeping mission on April 10. (Alexis Huguet/AFP/Getty Images)

The second Liberian civil war began 20 years ago this month. All told, the conflicts that ravaged Liberia from the beginning of the first civil war in 1989 to the end of the second in 2003 resulted in the deaths of some 250,000 men, women and children, the displacement of more than 1 million civilians and the destruction of much of the country’s infrastructure.

The United Nations Mission in Liberia (UNMIL) deployed in 2003 to help the country rebuild, and stayed until its mandate ended last year. By most accounts UNMIL was a success, shepherding in over a decade of peace and three consecutive democratic elections. What do we know now about the effects of international intervention to keep peace and restore the rule of law in Liberia and other war-wracked nations?

In a recent article in International Organization, I argue that one of UNMIL’s most important legacies is also one of its most underappreciated. Beyond the lives lost and livelihoods destroyed, the Liberian civil wars shattered the already-strained relationship between citizens and the Liberian government, especially the police and courts.

By the time the fighting stopped in 2003, few Liberians trusted the government to protect them from threats or help them resolve disputes. Where the rule of law is strong, citizens are willing to rely on the police and courts when crimes are committed or violence occurs.

In Liberia, that trust was gone

UNMIL was instrumental in repairing this broken social contract. The mission restructured the police and courts from the ground up, recruiting officers and judges and deploying them to posts around the country. Equally important, UNMIL engaged with citizens on a face-to-face, day-to-day basis to persuade them to give the police and courts another chance.

UNMIL conducted public awareness campaigns to spread the word about ongoing security and justice sector reforms. It organized town hall meetings to encourage cooperation with the police. And it helped the police reestablish contact with citizens through joint patrols and co-deployments in the most remote regions of the country.

These efforts paid off. In my research I draw on surveys with more than 13,000 Liberians between 2008 and 2012. The surveys served multiple purposes. They were the basis for an evaluation of an alternative dispute resolution program in Liberia, and for a pilot early warning system for riots and other types of local violence. But the surveys also produced a wealth of data on Liberians’ attitudes towards their own government, as well as their interactions with UNMIL personnel.

UNMIL helped restore confidence in the rule of law

Here’s what I discovered: The more frequently citizens interacted with UNMIL personnel, the more willing they were to rely on the police and courts to adjudicate the most serious incidents of crime and violence. Like other studies documenting the effects of seemingly mundane peacekeeping activities, I find that UNMIL’s impact depended in part on routine patrols, public works projects and interventions to resolve disputes.

I also find that UNMIL’s presence reduced reliance on the Liberian practice of “trial by ordeal” — an illegal but still widely used method to determine the identity of suspected criminals. In one common variation, a heated cutlass is pressed against the skin of the accused. If he burns, he’s guilty; if not, innocent.

The United Nations has long viewed trial by ordeal as a violation of human rights and due process protections. While UNMIL did not eradicate the practice, the mission helped reduce its prevalence.

My results echo the findings of several other studies testing UNMIL’s impact at the local level. Recent research has shown that UNMIL’s presence strengthened the vote share of national over “parochial” candidates for political office, and increased Liberians’ interest in politics and faith in the political process.

UNMIL training also paved the way for Liberian police officers to conduct outreach of their own through initiatives like the Confidence Patrols program, which further closed the gap between citizens and the police. These studies complement other work showing the local benefits of peacekeeping in Mali, Haiti, Cote d’Ivoire and elsewhere.

UNMIL personnel were hardly saints, however

UNMIL troops and police officers engaged in transactional sex with Liberian women, exhibited bias against members of particular ethnic or religious groups and were sometimes slow to respond to emerging threats, especially in the early days of the peacekeeping mandate. And, even after 15 years of reform, the Liberian police and courts remain rife with corruption and petty bribe-seeking.

Some commentators, including high-level U.S. policymakers, have pointed to problems like these as evidence of peacekeeping failure. But criticism of UNMIL’s shortcomings may obscure a record of often remarkable success.

The question is not whether Liberian institutions are now perfectly functional — they are not — or whether citizens’ trust in them has been completely restored. It has not. Instead, perhaps the question to ask today, 20 years after violence broke out anew, is whether Liberia is better off than it would have been had UNMIL never deployed, and whether the investment in peace and the rule of law was worth it.

Robert A. Blair (@robert_a_blair)i s the Joukowsky Family Assistant Professor of Political Science and International and Public Affairs at Brown University, and also a Junior Faculty Fellow in Stanford’s Center for International Security and Cooperation. His research focuses on international intervention and the consolidation of state authority after civil war, with an emphasis on rule of law and security institutions.